[bcc] Add macros to check libbcc version

Summary: Currently, libbcc only exposes its version via a string constant.
This makes it complicated for libraries built on top of libbcc to be compatible across multiple versions when there is API changes for instances, as happens in iovisor/gobpf#311

Exposing MAJOR/MINOR/PATCH versions would allow libraries which are not shipped as part of iovisor/bcc to handle those API changes.

This diffs exposes those values, provides a macro to perform version comparison (a la `LINUX_VERSION()`).

One thing it does not address currently is exposing whether this is an "exact tag" version, e.g a release, or in between releases.

Test plan:

When building:
```
-- Latest recognized Git tag is v0.24.0
-- Git HEAD is f26cdb33068187d04d9dc058834985df841e28fa
-- Revision is 0.24.0-f26cdb33 (major 0, minor 24, patch 0)
-- Found LLVM: /usr/lib/llvm-11/include 11.1.0 (Use LLVM_ROOT envronment variable for another version of LLVM)
...
...
```

and the produced `bcc_version.h`:
```
$ cat build/src/cc/bcc_version.h

```

update debian changelog for release v0.24.0

  * Support for kernel up to 5.16
  * bcc tools: update for trace.py, sslsniff.py, tcptop.py, hardirqs.py, etc.
  * new libbpf tools: bashreadline
  * allow specify wakeup_events for perf buffer
  * support BPF_MAP_TYPE_{INODE, TASK}_STORAGE maps
  * remove all deprecated libbpf function usage
  * remove P4/B language support
  * major test infra change, using github actions now
  * doc update, bug fixes and other tools improvement

Signed-off-by: Yonghong Song <yhs@fb.com>

update debian changelog for release v0.23.0

  * Support for kernel up to 5.15
  * bcc tools: update for kvmexit.py, tcpv4connect.py, cachetop.py, cachestat.py, etc.
  * libbpf tools: update for update for mountsnoop, ksnoop, gethostlatency, etc.
  * fix renaming of task_struct->state
  * get pid namespace properly for a number of tools
  * initial work for more libbpf utilization (less section names)
  * doc update, bug fixes and other tools improvement

Signed-off-by: Yonghong Song <yhs@fb.com>

update debian changelog for release v0.22.0

  * Support for kernel up to 5.14
  * add ipv4/ipv6 filter support for tcp trace tools
  * add python interface to attach raw perf events
  * fix tcpstates for incorrect display of dport
  * new options for bcc tools runqslower, argdist
  * new libbpf-tools: filetop, exitsnoop, tcprtt
  * doc update, bug fixes and other tools improvement

Signed-off-by: Yonghong Song <yhs@fb.com>

update debian changelog for release v0.21.0

  * Support for kernel up to 5.13
  * support for debug information from libdebuginfod
  * finished support for map elements items_*_batch() APIs
  * add atomic_increment() API
  * support attach_func() and detach_func() in python
  * fix displaying PID instead of TID for many tools
  * new tools: kvmexit.py
  * new libbpf-tools: gethostlatency, statsnoop, fsdist and solisten
  * fix tools ttysnoop/readahead for newer kernels
  * doc update and bug fixes

Signed-off-by: Yonghong Song <yhs@fb.com>

update debian changelog for release v0.20.0

  * Support for kernel up to 5.12
  * Some basic support for MIPS
  * added bpf_map_lookup_batch and bpf_map_delete_batch support
  * tools/funclatency.py support nested or recursive functions
  * tools/biolatency.py can optionally print out average/total value
  * fix possible marco HAVE_BUILTIN_BSWAP redefine warning for kernel >= 5.10.
  * new tools: virtiostat
  * new libbpf-tools: ext4dist
  * doc update and bug fixes

Signed-off-by: Yonghong Song <yhs@fb.com>

update debian changelog for release v0.19.0

  * Support for kernel up to 5.11
  * allow BCC as a cmake subproject
  * add LPORT support in tcpconnlat and tcpconnect
  * added bpf_map_lookup_and_delete_batch support
  * new tools: virtiostat
  * new libbpf-tools: cpufreq, funclatency, cachestat
  * add install target to libbpf-tools
  * a few lua fixes
  * doc update and bug fixes

Signed-off-by: Yonghong Song <yhs@fb.com>

update debian changelog for release v0.18.0

 * Support for kernel up to 5.10
 * add bpf kfunc/kretfunc C++ example
 * add PT_REGS_PARMx_SYSCALL helper macro
 * biolatency: allow json output
 * biolatpcts: support measuring overall latencies between two events
 * fix build when ENABLE_CLANG_JIT is disabled
 * doc update and bug fixes

Signed-off-by: Yonghong Song <yhs@fb.com>

update debian changelog for release v0.17.0

 * Support for kernel up to 5.9
 * usdt: add uprobe refcnt support
 * use newer llvm/clang versions in debian packaging if possible
 * add bpf iterator C++ support
 * new bcc tools: tcprtt, netqtop, swapin, tcpsynbl, threadsnoop
 * tcpconnect: add DNS correlation to connect tracking
 * new libbpf-tools: llcstat, numamove, runqlen, runqlat, softirgs, hardirqs
 * doc update, bug fixes and some additional arguments for tools

Signed-off-by: Yonghong Song <yhs@fb.com>

prepare for release v0.16.0

add changelog for release v0.16.0

Signed-off-by: Yonghong Song <yhs@fb.com>