f2fs: fix to clear GCed flag for atomic written page

Atomic write page can be GCed, after committing this kind of page, we should
clear the GCed flag for it.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/segment.c

@@ -253,6 +253,7 @@ int commit_inmem_pages(struct inode *inode, bool abort)
 					unlock_page(cur->page);
 					break;
 				}
+				clear_cold_data(cur->page);
 				submit_bio = true;
 			}
 		} else {