MEDIUM: pattern: change the pattern data integer from unsigned to signed

Till now the pattern data integer type was unsigned without any
particular reason. In order to make ACLs use it, we must switch it
to signed int instead.

include/types/pattern.h

@@ -70,7 +70,7 @@ struct pattern_arg {
 union pattern_data {
 	struct in_addr ip;        /* used for ipv4 type */
 	struct in6_addr ipv6;     /* used for ipv6 type */
-	uint32_t integer;         /* used for unsigned 32bits integer type */
+	int integer;              /* used for unsigned 32bits integer type */
 	struct chunk str;         /* used for char string type or buffers*/
 };