f2fs: add sbi and page pointer in f2fs_io_info

This patch adds f2fs_sb_info and page pointers in f2fs_io_info structure.
With this change, we can reduce a lot of parameters for IO functions.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/file.c

@@ -271,7 +271,7 @@ flush_out:
 	ret = f2fs_issue_flush(sbi);
 out:
 	trace_f2fs_sync_file_exit(inode, need_cp, datasync, ret);
-	f2fs_trace_ios(NULL, NULL, 1);
+	f2fs_trace_ios(NULL, 1);
 	return ret;
 }