sb/intel: Use common RCBA MACROs

This commit follows up on commit 2e464cf3 with Change-Id
I61fb3b01ff15ba2da2ee938addfa630c282c9870.

Change-Id: Iaf06d347e2da5680816b17f49523ac1a687798ba
Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>
Reviewed-on: https://review.coreboot.org/c/29236
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: HAOUAS Elyes <ehaouas@noos.fr>
Reviewed-by: David Guckian
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/southbridge/intel/ibexpeak/pch.h

@@ -227,9 +227,6 @@ void southbridge_configure_default_intmap(void);
 
 #define PMBASE		0x40
 
-/* Root Complex Register Block */
-#define RCBA		0xf0
-
 #define VCH		0x0000	/* 32bit */
 #define VCAP1		0x0004	/* 32bit */
 #define VCAP2		0x0008	/* 32bit */