After I modify the pci_ext_read_config32 and pci_ext_read_config32, the step 6a

After I modify the pci_ext_read_config32 and pci_ext_read_config32, the step 6a
starts to play its role. Then the system hangs at HDA init. I dont know what the
VC1 is. The RPR says "Optional Features (only needed if CMOS option is enabled)"
in 5.10.2. Before I know what it is, I think it is better to skip it.

Tested on dbm690t.

Add comment from Rudolf,
"
VC is virtual channel. Its used for isochronous transfer of data to sound card.
The virtual channel guarantee "on time" delivery. In other words it sets up a
channel for data to sound card, which means that that arrivs in time and there will
be no interuptions in audio stream.

http://www.microsoft.com/whdc/connect/pci/wlp_interrupt.mspx
"

Signed-off-by: Zheng Bao <zheng.bao@amd.com>
Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@4339 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1