add more BTRFS support

[Gene Czarcinski]

Currently, using BTRFS subvolumes for root, boot, or root+boot seem to 
be working for the system being updated (except for the small problem 
with multi-device btrfs volumes which are addressed in another bug report).

However, support for BTRFS systems by os-prober is non-existent. Based 
on Fedora 18, I have developed some patches for os-prober and 
linux-boot-prober to handle btrfs and pass information back to 
30_os-prober.  Then, a small change to 30_os-prober is needed to 
complete the additional support.

This is covered by two bugzilla reports:
https://bugzilla.redhat.com/show_bug.cgi?id=890987
https://bugzilla.redhat.com/show_bug.cgi?id=888341

The patches to the os-prober package have been sent upstream.

In addition, attached are the proposed patches.

Gene

0001-Add-btrfs-support-for-root-and-boot-on-a-subvolume.patch
Description: Text Data

os-prober-fix-btrfs-1.336.patch
Description: Text Data