msm_shared: Fix crypto eng hash calculation issue

crypto engine was generating incorrect hash for the kernel
image, due to crypto registers not cleared as the crypto reset
did not happen properly. Use memory barriers to ensure writes
are complete to the crypto engine registers.

CRs-Fixed: 355744
Change-Id: Iea1f5cd64ba314ab1490e8705dc45a5ac7c24c23
diff --git a/platform/msm_shared/crypto_eng.c b/platform/msm_shared/crypto_eng.c
index 4360742..76aa714 100644
--- a/platform/msm_shared/crypto_eng.c
+++ b/platform/msm_shared/crypto_eng.c
@@ -41,6 +41,7 @@
 void crypto_eng_reset(void)
 {
 	wr_ce(SW_RST, CRYPTO3_CONFIG);
+	dmb();
 }
 
 /*