cifs: Allow passwords which begin with a delimitor

commit c369c9a4a7c82d33329d869cbaf93304cc7a0c40 upstream.

Fixes a regression in cifs_parse_mount_options where a password
which begins with a delimitor is parsed incorrectly as being a blank
password.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>