crypto, x86: aesni - fix token pasting for clang

aes_ctrby8_avx-x86_64.S uses the C preprocessor for token pasting
of character sequences that are not valid preprocessor tokens.
While this is allowed when preprocessing assembler files it exposes
an incompatibilty between the clang and gcc preprocessors where
clang does not strip leading white space from macro parameters,
leading to the CONCAT(%xmm, i) macro expansion on line 96 resulting
in a token with a space character embedded in it.

While this could be resolved by deleting the offending space character,
the assembler is perfectly capable of doing the token pasting correctly
for itself so we can just get rid of the preprocessor macros.

Signed-off-by: Michael Davidson <md@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>