net/sunrpc: Use static const char arrays

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/auth_gss/gss_krb5_mech.c

@@ -422,7 +422,7 @@ static int
 context_derive_keys_rc4(struct krb5_ctx *ctx)
 {
 	struct crypto_hash *hmac;
-	char sigkeyconstant[] = "signaturekey";
+	static const char sigkeyconstant[] = "signaturekey";
 	int slen = strlen(sigkeyconstant) + 1;	/* include null terminator */
 	struct hash_desc desc;
 	struct scatterlist sg[1];