f2fs: remove unnecessary condition checks

This patch removes the unnecessary condition checks on:

fs/f2fs/gc.c:667 do_garbage_collect() warn: 'sum_page' isn't an ERR_PTR
fs/f2fs/f2fs.h:795 f2fs_put_page() warn: 'page' isn't an ERR_PTR
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

fs/f2fs/f2fs.h

@@ -792,7 +792,7 @@ static inline unsigned int valid_inode_count(struct f2fs_sb_info *sbi)
 
 static inline void f2fs_put_page(struct page *page, int unlock)
 {
-	if (!page || IS_ERR(page))
+	if (!page)
 		return;
 
 	if (unlock) {

fs/f2fs/gc.c

@@ -664,8 +664,6 @@ static void do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno,
 
 	/* read segment summary of victim */
 	sum_page = get_sum_page(sbi, segno);
-	if (IS_ERR(sum_page))
-		return;
 
 	blk_start_plug(&plug);