[SeaBIOS] seabios stable release

[Gerd Hoffmann]

  Hi,

Looks like we need a stable release branch for 1.8 and roll out a 1.8.1
release with some fixes for qemu.

Issue #1: support for multiple pci roots.

Issue #2: There is a (not-yet fixed) emulation failure with newer intel
processors, apparently triggered by seabios commit
0673b7870063a3affbad9046fb6d385a4e734c19

Thread starts here:
  https://lists.gnu.org/archive/html/qemu-devel/2015-03/msg01140.html

Other known issues in 1.8 which should be addressed in 1.8.1?

cheers,
  Gerd