crypto: x86/aria-avx - fix build failure with old binutils

The minimum version of binutils for kernel build is currently 2.23 and
it doesn't support GFNI.
So, it fails to build the aria-avx if the old binutils is used.
The code using GFNI is an optional part of aria-avx.
So, it disables GFNI part in it when the old binutils is used.
In order to check whether the using binutils is supporting GFNI or not,
AS_GFNI is added.

Fixes: ba3579e6 ("crypto: aria-avx - add AES-NI/AVX/x86_64/GFNI assembler implementation of aria cipher")
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>