sb/intel/lynxpoint: Add native USB init

Implement native USB initialisation for Lynx Point. This is only needed
when MRC.bin is not used.

TO DO: Figure out how to deal with the FIXME's and TODO's lying around.

Change-Id: Ie0fbeeca7b1ca1557173772d733fd2fa27703373
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64179
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/src/southbridge/intel/lynxpoint/Makefile.inc b/src/southbridge/intel/lynxpoint/Makefile.inc
index 49f03f1..14bba2e1 100644
--- a/src/southbridge/intel/lynxpoint/Makefile.inc
+++ b/src/southbridge/intel/lynxpoint/Makefile.inc
@@ -35,7 +35,7 @@
 romstage-y += early_usb.c early_me.c me_status.c early_pch.c
 romstage-y += pmutil.c
 
-romstage-$(CONFIG_USE_NATIVE_RAMINIT) += early_pch_native.c
+romstage-$(CONFIG_USE_NATIVE_RAMINIT) += early_pch_native.c early_usb_native.c iobp.c
 
 ifeq ($(CONFIG_INTEL_LYNXPOINT_LP),y)
 romstage-y += lp_gpio.c