bpf: Fix early return in map_check_btf

Instead of returning directly with -EOPNOTSUPP for the timer case, we
need to free the btf_record before returning to userspace.

Fixes: db559117 ("bpf: Consolidate spin_lock, timer management into btf_record")
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-2-memxor@gmail.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>

kernel/bpf/syscall.c

@@ -1010,7 +1010,7 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
 				if (map->map_type != BPF_MAP_TYPE_HASH &&
 				    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
 				    map->map_type != BPF_MAP_TYPE_ARRAY) {
-					return -EOPNOTSUPP;
+					ret = -EOPNOTSUPP;
 					goto free_map_tab;
 				}
 				break;