tools/resolve_btfids: Fix comparison of distinct pointer types warning in resolve_btfids

Add a type cast for set8->pairs to fix below compile warning:

main.c: In function 'sets_patch':
main.c:699:50: warning: comparison of distinct pointer types lacks a cast
699 | BUILD_BUG_ON(set8->pairs != &set8->pairs[0].id);
| ^~

Fixes: 9707ac4fe2f5 ("tools/resolve_btfids: Refactor set sorting with types from btf_ids.h")
Signed-off-by: Liwei Song <[e-mail]>
Signed-off-by: Daniel Borkmann <[e-mail]>
Acked-by: Jiri Olsa <[e-mail]>
Link: https://lore.kernel.org/bpf/[e-mail]

tools/bpf/resolve_btfids/main.c

···
 			 * Make sure id is at the beginning of the pairs
 			 * struct, otherwise the below qsort would not work.
 			 */
-			BUILD_BUG_ON(set8->pairs != &set8->pairs[0].id);
+			BUILD_BUG_ON((u32 *)set8->pairs != &set8->pairs[0].id);
 			qsort(set8->pairs, set8->cnt, sizeof(set8->pairs[0]), cmp_id);
 
 			/*