CLEANUP: Consistently `unsigned int` for bitfields

Signed bitfields of size `1` hold the values `0` and `-1`, but are
usually assigned `1`, possibly leading to subtle bugs when the value
is explicitely compared against `1`.
diff --git a/include/types/pattern.h b/include/types/pattern.h
index a0bb08e..a2d609b 100644
--- a/include/types/pattern.h
+++ b/include/types/pattern.h
@@ -150,8 +150,8 @@
 		int i;                          /* integer value */
 		struct {
 			signed long long min, max;
-			int min_set :1;
-			int max_set :1;
+			unsigned int min_set:1;
+			unsigned int max_set:1;
 		} range; /* integer range */
 		struct {
 			struct in_addr addr;