net/sunrpc/auth_gss/gss_krb5_crypto.c: Use normal negative error value return

And remove unnecessary double semicolon too.

No effect to code, as test is != 0.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

net/sunrpc/auth_gss/gss_krb5_crypto.c

@@ -137,7 +137,7 @@ arcfour_hmac_md5_usage_to_salt(unsigned int usage, u8 salt[4])
 		ms_usage = 13;
 		break;
 	default:
-		return EINVAL;;
+		return -EINVAL;
 	}
 	salt[0] = (ms_usage >> 0) & 0xff;
 	salt[1] = (ms_usage >> 8) & 0xff;