tinycrypt/sha256: Array compared to NULL has no effect

This commit fixes the issue reported by Coverity/Zephyr: an array
compared against NULL is always false.

Coverity-CID: 143715
Coverity-CID: 143730

Change-Id: Ia502736f605774b71c1a41a850b84663c78fc7d0
Signed-off-by: Flavio Santes <[email protected]>

Author: 1010101001010101

lib/source/sha256.c

@@ -66,7 +66,6 @@ int32_t tc_sha256_update(TCSha256State_t s, const uint8_t *data, size_t datalen)
 {
 	/* input sanity check: */
 	if (s == (TCSha256State_t) 0 ||
-	    s->iv == (uint32_t *) 0 ||
 	    data == (void *) 0) {
 		return TC_CRYPTO_FAIL;
 	} else if (datalen == 0) {
@@ -91,8 +90,7 @@ int32_t tc_sha256_final(uint8_t *digest, TCSha256State_t s)
 
 	/* input sanity check: */
 	if (digest == (uint8_t *) 0 ||
-	    s == (TCSha256State_t) 0 ||
-	    s->iv == (uint32_t *) 0) {
+	    s == (TCSha256State_t) 0) {
 		return TC_CRYPTO_FAIL;
 	}