Clean up ARM (klauspost#48)

* Clean up ARM stuff.

Add raw vendor string (klauspost#43)

Fixes klauspost#42

Tweaks.

Fix SGX tests. (klauspost#39)

There might be cases where an SGX-enabled device hasn't got SGX EPC
subleafs. However, if there are such leaves, the total amount of memory
must not be 0.

Signed-off-by: Ismo Puustinen <ismo.puustinen@intel.com>

Merge pull request klauspost#32 from mythi/vnni

Add AVX512-VNNI detection

Add v1.2.0 tag

Merge pull request klauspost#10 from klauspost/disable-gccgo-build

Disable assembly build on gccgo.