gcm_ghash_4bit
void gcm_ghash_4bit(u64 Xi[2], const u128 Htable[16], const u8 *inp,
ctx->ghash = gcm_ghash_4bit;
ctx->ghash = gcm_ghash_4bit;
ctx->ghash = gcm_ghash_4bit;
ctx->ghash = gcm_ghash_4bit;
ctx->ghash = gcm_ghash_4bit;
ctx->ghash = gcm_ghash_4bit;