f2fs: split drop_inmem_pages from commit_inmem_pages

Split drop_inmem_pages from commit_inmem_pages for code readability,
and prepare for the following modification.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index a4362d4..92273b6 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -1252,7 +1252,7 @@
 {
 	/* some remained atomic pages should discarded */
 	if (f2fs_is_atomic_file(inode))
-		commit_inmem_pages(inode, true);
+		drop_inmem_pages(inode);
 	if (f2fs_is_volatile_file(inode)) {
 		set_inode_flag(F2FS_I(inode), FI_DROP_CACHE);
 		filemap_fdatawrite(inode->i_mapping);
@@ -1376,7 +1376,7 @@
 
 	if (f2fs_is_atomic_file(inode)) {
 		clear_inode_flag(F2FS_I(inode), FI_ATOMIC_FILE);
-		ret = commit_inmem_pages(inode, false);
+		ret = commit_inmem_pages(inode);
 		if (ret) {
 			set_inode_flag(F2FS_I(inode), FI_ATOMIC_FILE);
 			goto err_out;
@@ -1439,7 +1439,7 @@
 
 	if (f2fs_is_atomic_file(inode)) {
 		clear_inode_flag(F2FS_I(inode), FI_ATOMIC_FILE);
-		commit_inmem_pages(inode, true);
+		drop_inmem_pages(inode);
 	}
 	if (f2fs_is_volatile_file(inode)) {
 		clear_inode_flag(F2FS_I(inode), FI_VOLATILE_FILE);