Merge remote-tracking branch 'remotes/kraxel/tags/pull-roms-1' into staging

Update seabios to 1.7.4

# gpg: Signature made Mon 03 Feb 2014 14:42:44 GMT using RSA key ID D3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <[email protected]>"
# gpg:                 aka "Gerd Hoffmann <[email protected]>"
# gpg:                 aka "Gerd Hoffmann (private) <[email protected]>"

* remotes/kraxel/tags/pull-roms-1:
  Update seabios binaries to 1.7.4
  Update seabios submodule to 1.7.4
  roms: remove explicit MAKEFLAGS from recursive make invocations

Signed-off-by: Peter Maydell <[email protected]>