qnx4fs: Use kmemdup rather than duplicating its implementation

The semantic patch that makes this change is available
in scripts/coccinelle/api/memdup.cocci.
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Anders Larsen <al@alarsen.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

fs/qnx4/inode.c

@@ -199,12 +199,13 @@ static const char *qnx4_checkroot(struct super_block *sb)
 					if (!strcmp(rootdir->di_fname,
 						    QNX4_BMNAME)) {
 						found = 1;
-						qnx4_sb(sb)->BitMap = kmalloc( sizeof( struct qnx4_inode_entry ), GFP_KERNEL );
+						qnx4_sb(sb)->BitMap = kmemdup(rootdir,
+									      sizeof(struct qnx4_inode_entry),
+									      GFP_KERNEL);
 						if (!qnx4_sb(sb)->BitMap) {
 							brelse (bh);
 							return "not enough memory for bitmap inode";
-						}
-						memcpy( qnx4_sb(sb)->BitMap, rootdir, sizeof( struct qnx4_inode_entry ) );	/* keep bitmap inode known */
+						}/* keep bitmap inode known */
 						break;
 					}
 				}