usbdebug: Use __SIMPLE_DEVICE__ on early enable

With USBDEBUG selected, the file is built for both romstage and
ramstage. For the ramstage build, we need to explicitly use the
simple PCI config operations without devicetree.

Change-Id: I2de8d9c77bb458ba797c3aac9e2cd0d653e06684
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/3437
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@google.com>
diff --git a/src/southbridge/sis/sis966/enable_usbdebug.c b/src/southbridge/sis/sis966/enable_usbdebug.c
index 78a3838..1ff04df 100644
--- a/src/southbridge/sis/sis966/enable_usbdebug.c
+++ b/src/southbridge/sis/sis966/enable_usbdebug.c
@@ -23,6 +23,9 @@
 
 /* TODO: Check whether this actually works (might be copy-paste leftover). */
 
+// Use simple device model for this file even in ramstage
+#define __SIMPLE_DEVICE__
+
 #include <stdint.h>
 #include <arch/io.h>
 #include <usbdebug.h>