OvmfPkg BDS: Remove support for loading vgabios-cirrus.bin from 0xc0000

OvmfPkg BDS: Remove support for loading vgabios-cirrus.bin from 0xc0000

Older QEMU versions would load vgabios-cirrus.bin at 0xc0000 in
system RAM. We would then find this ROM, and try to run it, since
it would be our QEMU Video driver.

Now, the QEMU Video driver is just merged into the main OVMF
firmware image, so this support is unused.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13522 6f19259b-4bc3-4df7-8a09-765794883524