Devices that can be used as raw kdump target

[Martin Milata]

system-config-kdump has hardcoded whitelist of major numbers for block
devices that can be used as raw kdump targets. With the current list it
does not show virtio disks [1] as possible targets. The major device
number for virtio is assigned dynamically, thus I cannot simply add a
new number.

I have no idea how the major numbers in the list were chosen. I see
these possibilities for fixing the bug:

* Do not try to outsmart the user, throw away the list, and offer all
  devices that are listed in /proc/partitions.

* Add all the numbers that can be used for dynamic assignment to the
  whitelist.

* Determine whether a device is suitable by some other means. For
  example, /sys/dev/block/MAJOR:MINOR/ro should contain 1 if the device
  is read-only. However it contains 0 for my optical drive, so using
  this is probably not as useful.

I'll be grateful for any suggestions,
Martin

[0] https://git.fedorahosted.org/cgit/system-config-kdump.git/tree/src/system-config-kdump.py#n80
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1077470