cpu/intel: Enter romstage without BIST

When entry to romstage is via cpu/intel/car/romstage.c
BIST has not been passed down the path for sometime.

Change-Id: I345975c53014902269cee21fc393331d33a84dce
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34908
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

src/include/cpu/intel/romstage.h

@@ -3,7 +3,7 @@
 
 #include <arch/cpu.h>
 
-void mainboard_romstage_entry(unsigned long bist);
+void mainboard_romstage_entry(void);
 
 /* fill_postcar_frame() is called after raminit completes and right before
  * calling run_postcar_phase(). Implementation should call postcar_frame_add_mtrr()