Revert "Linux: Fix zfs_prune panics"

This reverts commit 6fb74ca.

module/os/linux/zfs/zpl_super.c

@@ -386,18 +386,7 @@ zpl_prune_sb(uint64_t nr_to_scan, void *arg)
 	struct super_block *sb = (struct super_block *)arg;
 	int objects = 0;
 
-	/*
-	 * deactivate_locked_super calls shrinker_free and only then
-	 * sops->kill_sb cb, resulting in UAF on umount when trying to reach
-	 * for the shrinker functions in zpl_prune_sb of in-umount dataset.
-	 * Increment if s_active is not zero, but don't prune if it is -
-	 * umount could be underway.
-	 */
-	if (atomic_inc_not_zero(&sb->s_active)) {
-		(void) -zfs_prune(sb, nr_to_scan, &objects);
-		atomic_dec(&sb->s_active);
-	}
-
+	(void) -zfs_prune(sb, nr_to_scan, &objects);
 }
 
 static int