Fix gcc 4.6.1 breakage of southbridge/amd/sr5650/pcie.c.

Fix gcc 4.6.1 breakage of southbridge/amd/sr5650/pcie.c.

Change-Id: I3ccb3860207e1b3ccac4313f7b537c434af5166f
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/360
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)
Reviewed-by: Rudolf Marek <r.marek@assembler.cz>