Warn if result of ts_set_flags_32 is not used

The ts_set_flags_32 function takes a bitmap and flags and returns an
updated bitmap. However, if the returned value is not used, the function
call has no effect. An unused result may indicate the improper use of this
function.

This patch adds the qualifier pg_nodiscard to the function which
triggers a warning if the returned value is not used.

src/utils.h

@@ -169,7 +169,7 @@ ts_flags_are_set_32(uint32 bitmap, uint32 flags)
 	return (bitmap & flags) == flags;
 }
 
-static inline uint32
+static inline pg_nodiscard uint32
 ts_set_flags_32(uint32 bitmap, uint32 flags)
 {
 	return bitmap | flags;