acpi: make fill_slit and fill_srat into arguments.

SLIT and SRAT are created this way only on amdk8 and amdfam10.
This saves the need of having a lot of dummies.

Change-Id: I76d042702209cd6d11ee78ac22cf9fe9d30d0ca5
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/7052
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/mainboard/google/slippy/acpi_tables.c

@@ -99,15 +99,3 @@ unsigned long acpi_fill_madt(unsigned long current)
 
 	return current;
 }
-
-unsigned long acpi_fill_slit(unsigned long current)
-{
-	// Not implemented
-	return current;
-}
-
-unsigned long acpi_fill_srat(unsigned long current)
-{
-	/* No NUMA, no SRAT */
-	return current;
-}