nb/intel/pineview: Remove dead assignments

The call to `decode_pciebar` always initializes these values.

Change-Id: Ide45e1e5e8b8d6cfebd2fc4e272b1971b0a9b346
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44119
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

src/northbridge/intel/pineview/acpi.c

@@ -8,8 +8,7 @@
 
 unsigned long acpi_fill_mcfg(unsigned long current)
 {
-	u32 length = 0;
-	u32 pciexbar = 0;
+	u32 length, pciexbar;
 	int max_buses;
 
 	if (!decode_pciebar(&pciexbar, &length))