udev: Two fixes
This update fixes the following issues for udev:
- bnc#783054: cdrom_id: created links for the default cd/dvd drive
- bnc#779493: usb_id: ensure we have a valid serial number as a string
- Submitted by Robert Milasan (rmilasan)
Fixed bugs
bnc#783054
openSUSE 12.2 - missing /dev/dvd symlink
bnc#779493
installer can not find installation repository (pb dots e2, samsung bd writer)