Remove uma_memory_base from build if no GFXUMA

This patch validates the previous "drop uma_memory_base" patches;
there are no more references to uma_memory_base when GFXUMA is not
selected.

Change-Id: I735b5e765b0c5cb4af1b4a7470cfe1af2bda7d38
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/1385
Tested-by: build bot (Jenkins)
Reviewed-by: Anton Kochkov <anton.kochkov@gmail.com>

src/devices/device.c

@@ -54,10 +54,11 @@ struct resource *free_resources = NULL;
 
 DECLARE_SPIN_LOCK(dev_lock)
 
-
+#if CONFIG_GFXUMA
 /* IGD UMA memory */
 uint64_t uma_memory_base = 0;
 uint64_t uma_memory_size = 0;
+#endif
 
 /**
  * Allocate a new device structure.