amd/cimx: fix sb(8|9)00 NULL type redefine

It is inappropriate for chipset code to be redefining
types -- especially NULL to a non-pointer type. There's
only one non-straight forward change. A condition
being checked was '!ptr_type == NULL' (0 as int). That
check is actually 'ptr_type != NULL'.

Change-Id: Iab5733e5a573baba6fec94e0c955ba4fad72c836
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/5088
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
diff --git a/src/vendorcode/amd/cimx/sb800/GEC.c b/src/vendorcode/amd/cimx/sb800/GEC.c
index 6ee142f..582181b 100644
--- a/src/vendorcode/amd/cimx/sb800/GEC.c
+++ b/src/vendorcode/amd/cimx/sb800/GEC.c
@@ -113,7 +113,7 @@
     ReadPCI ((GEC_BUS_DEV_FUN << 16) + SB_GEC_REG04, AccWidthUint8, &dbVar);
     dbTemp = 0x07;
     WritePCI ((GEC_BUS_DEV_FUN << 16) + SB_GEC_REG04, AccWidthUint8, &dbTemp);
-    if ( !pConfig->DYNAMICGECROM.DynamicGecRomAddress_Ptr == NULL ) {
+    if ( pConfig->DYNAMICGECROM.DynamicGecRomAddress_Ptr != NULL ) {
       GecRomAddress = pConfig->DYNAMICGECROM.DynamicGecRomAddress_Ptr;
       GecShadowRomAddress = (VOID*) (UINTN) pConfig->BuildParameters.GecShadowRomBase;
       AmdSbCopyMem (GecShadowRomAddress, GecRomAddress, 0x100);