biology/hhsuite: fix build on powerpc64 elfv2

Use GCC instead of Clang:
/usr/lib/clang/10.0.0/include/mmintrin.h:216:19: error: use of undeclared identifier '__builtin_ia32_punpckhbw'

return (__m64)__builtin_ia32_punpckhbw((__v8qi)__m1, (__v8qi)__m2);