Fix number parsing in cifs_parse_mount_options

The function kstrtoul() used to parse number strings in the mount
option parser is set to expect a base 10 number . This treats the octal
numbers passed for mount options such as file_mode as base10 numbers
leading to incorrect behavior.

Change the 'base' argument passed to kstrtoul from 10 to 0 to
allow it to auto-detect the base of the number passed.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Acked-by: Jeff Layton <jlayton@samba.org>
Reported-by: Chris Clayton <chris2553@googlemail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>