Staging/pohmelfs: fix write_inode parameter warning

sparse warns that:
drivers/staging/pohmelfs/inode.c:1797: warning: initialization from incompatible pointer type

so fix pohmelfs_write_inode() to have the expected parameters.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/pohmelfs/inode.c

@@ -396,7 +396,8 @@ int pohmelfs_remove_child(struct pohmelfs_inode *pi, struct pohmelfs_name *n)
 /*
  * Writeback for given inode.
  */
-static int pohmelfs_write_inode(struct inode *inode, int sync)
+static int pohmelfs_write_inode(struct inode *inode,
+				struct writeback_control *wbc)
 {
 	struct pohmelfs_inode *pi = POHMELFS_I(inode);