GCM: move Intel PCLMUL accelerated implementation to separate file

* cipher/Makefile.am: Add 'cipher-gcm-intel-pclmul.c'.
* cipher/cipher-gcm-intel-pclmul.c: New.
* cipher/cipher-gcm.c [GCM_USE_INTEL_PCLMUL]
(_gcry_ghash_setup_intel_pclmul, _gcry_ghash_intel_pclmul): New
prototypes.
[GCM_USE_INTEL_PCLMUL] (gfmul_pclmul, gfmul_pclmul_aggr4): Move
to 'cipher-gcm-intel-pclmul.c'.
(ghash): Rename to...
(ghash_internal): ...this and move GCM_USE_INTEL_PCLMUL part to new
function in 'cipher-gcm-intel-pclmul.c'.
(setupM): Move GCM_USE_INTEL_PCLMUL part to new function in
'cipher-gcm-intel-pclmul.c'; Add selection of ghash function based
on available HW acceleration.
(do_ghash_buf): Change use of 'ghash' to 'c->u_mode.gcm.ghash_fn'.
* cipher/internal.h (ghash_fn_t): New.
(gcry_cipher_handle): Remove 'use_intel_pclmul'; Add 'ghash_fn'.
--

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
rijndael: further optimizations for AES-NI accelerated CBC and CFB bulk modes

* cipher/rijndael-aesni.c (do_aesni_enc, do_aesni_dec): Pass
input/output through SSE register XMM0.
(do_aesni_cfb): Remove.
(_gcry_aes_aesni_encrypt, _gcry_aes_aesni_decrypt): Add loading/storing
input/output to/from XMM0.
(_gcry_aes_aesni_cfb_enc, _gcry_aes_aesni_cbc_enc)
(_gcry_aes_aesni_cfb_dec): Update to use renewed 'do_aesni_enc' and
move IV loading/storing outside loop.
(_gcry_aes_aesni_cbc_dec): Update to use renewed 'do_aesni_dec'.
--

CBC encryption speed is improved ~16% on Intel Haswell and CFB encryption ~8%.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>