crypto: x86/sha256-avx2 - add missing vzeroupper

[ Upstream commit 57ce8a4 ]

Since sha256_transform_rorx() uses ymm registers, execute vzeroupper
before returning from it.  This is necessary to avoid reducing the
performance of SSE code.

Fixes: d34a460 ("crypto: sha256 - Optimized sha256 x86_64 routine using AVX2's RORX instructions")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>

arch/x86/crypto/sha256-avx2-asm.S

@@ -711,6 +711,7 @@ done_hash:
 	popq	%r13
 	popq	%r12
 	popq	%rbx
+	vzeroupper
 	RET
 SYM_FUNC_END(sha256_transform_rorx)