* cipher/Makefile.am: Add 'rijndael-ppc.c'.
* cipher/rijndael-internal.h (USE_PPC_CRYPTO): New.
(RIJNDAEL_context): Add 'use_ppc_crypto'.
* cipher/rijndael-ppc.c (backwards, swap_if_le): Remove.
(u128_t, ALWAYS_INLINE, NO_INLINE, NO_INSTRUMENT_FUNCTION)
(ASM_FUNC_ATTR, ASM_FUNC_ATTR_INLINE, ASM_FUNC_ATTR_NOINLINE)
(ALIGNED_LOAD, ALIGNED_STORE, VEC_LOAD_BE, VEC_STORE_BE)
(vec_bswap32_const, vec_aligned_ld, vec_load_be_const)
(vec_load_be, vec_aligned_st, vec_store_be, _gcry_aes_sbox4_ppc8)
(_gcry_aes_ppc8_setkey, _gcry_aes_ppc8_prepare_decryption)
(aes_ppc8_encrypt_altivec, aes_ppc8_decrypt_altivec): New.
(_gcry_aes_ppc8_encrypt, _gcry_aes_ppc8_decrypt): Rewrite.
(_gcry_aes_ppc8_ocb_crypt): Comment out.
* cipher/rijndael.c [USE_PPC_CRYPTO] (_gcry_aes_ppc8_setkey)
(_gcry_aes_ppc8_prepare_decryption, _gcry_aes_ppc8_encrypt)
(_gcry_aes_ppc8_decrypt): New prototypes.
(do_setkey) [USE_PPC_CRYPTO]: Add setup for PowerPC AES.
(prepare_decryption) [USE_PPC_CRYPTO]: Ditto.
* configure.ac: Add 'rijndael-ppc.lo'.
(gcry_cv_ppc_altivec, gcry_cv_cc_ppc_altivec_cflags)
(gcry_cv_gcc_inline_asm_ppc_altivec)
(gcry_cv_gcc_inline_asm_ppc_arch_3_00): New checks.

 ECB enc |      7.27 ns/B     131.2 MiB/s     27.61 c/B
 ECB dec |      7.70 ns/B     123.8 MiB/s     29.28 c/B
 CBC enc |      6.38 ns/B     149.5 MiB/s     24.24 c/B
 CBC dec |      6.17 ns/B     154.5 MiB/s     23.45 c/B
 CFB enc |      6.45 ns/B     147.9 MiB/s     24.51 c/B
 CFB dec |      6.20 ns/B     153.8 MiB/s     23.57 c/B
 OFB enc |      7.36 ns/B     129.6 MiB/s     27.96 c/B
 OFB dec |      7.36 ns/B     129.6 MiB/s     27.96 c/B
 CTR enc |      6.22 ns/B     153.2 MiB/s     23.65 c/B
 CTR dec |      6.22 ns/B     153.3 MiB/s     23.65 c/B
 XTS enc |      6.67 ns/B     142.9 MiB/s     25.36 c/B
 XTS dec |      6.70 ns/B     142.3 MiB/s     25.46 c/B
 CCM enc |     12.61 ns/B     75.60 MiB/s     47.93 c/B
 CCM dec |     12.62 ns/B     75.56 MiB/s     47.96 c/B
CCM auth |      6.41 ns/B     148.8 MiB/s     24.36 c/B
 EAX enc |     12.62 ns/B     75.55 MiB/s     47.96 c/B
 EAX dec |     12.62 ns/B     75.55 MiB/s     47.97 c/B
EAX auth |      6.39 ns/B     149.2 MiB/s     24.30 c/B
 GCM enc |      9.81 ns/B     97.24 MiB/s     37.27 c/B
 GCM dec |      9.81 ns/B     97.20 MiB/s     37.28 c/B
GCM auth |      3.59 ns/B     265.8 MiB/s     13.63 c/B
 OCB enc |      6.39 ns/B     149.3 MiB/s     24.27 c/B
 OCB dec |      6.38 ns/B     149.5 MiB/s     24.25 c/B
OCB auth |      6.35 ns/B     150.2 MiB/s     24.13 c/B

 ECB enc |      1.29 ns/B     737.7 MiB/s      4.91 c/B
 ECB dec |      1.34 ns/B     711.1 MiB/s      5.10 c/B
 CBC enc |      2.13 ns/B     448.5 MiB/s      8.08 c/B
 CBC dec |      1.05 ns/B     908.0 MiB/s      3.99 c/B
 CFB enc |      2.17 ns/B     439.9 MiB/s      8.24 c/B
 CFB dec |      2.22 ns/B     429.8 MiB/s      8.43 c/B
 OFB enc |      1.49 ns/B     640.1 MiB/s      5.66 c/B
 OFB dec |      1.49 ns/B     640.1 MiB/s      5.66 c/B
 CTR enc |      2.21 ns/B     432.5 MiB/s      8.38 c/B
 CTR dec |      2.20 ns/B     432.5 MiB/s      8.38 c/B
 XTS enc |      2.32 ns/B     410.6 MiB/s      8.83 c/B
 XTS dec |      2.33 ns/B     409.7 MiB/s      8.85 c/B
 CCM enc |      4.36 ns/B     218.7 MiB/s     16.57 c/B
 CCM dec |      4.36 ns/B     218.8 MiB/s     16.56 c/B
CCM auth |      2.17 ns/B     440.4 MiB/s      8.23 c/B
 EAX enc |      4.37 ns/B     218.3 MiB/s     16.60 c/B
 EAX dec |      4.36 ns/B     218.7 MiB/s     16.57 c/B
EAX auth |      2.16 ns/B     440.7 MiB/s      8.22 c/B
 GCM enc |      5.78 ns/B     165.0 MiB/s     21.96 c/B
 GCM dec |      5.78 ns/B     165.0 MiB/s     21.96 c/B
GCM auth |      3.59 ns/B     265.9 MiB/s     13.63 c/B
 OCB enc |      2.33 ns/B     410.1 MiB/s      8.84 c/B
 OCB dec |      2.34 ns/B     407.2 MiB/s      8.90 c/B
OCB auth |      2.32 ns/B     411.1 MiB/s      8.82 c/B