chacha20/AVX2: check for ENABLE_AVX2_SUPPORT instead of HAVE_GCC_INLINE_ASM_AVX2
* cipher/chacha20.c (USE_AVX2): Enable depending on ENABLE_AVX2_SUPPORT, not HAVE_GCC_INLINE_ASM_AVX2. * cipher/chacha20-avx2-amd64.S: Ditto.
- Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>