nb/intel/gm45: Remove UMA alignment optimization

This code path was only triggered in one corner case: GFX UMA set to
48MiB. It created a hole below UMA to save MTRRs. But, this hole was
never accounted for when calculating cbmem_top(). Instead of trying
to fix it, remove it, it's not worth the trouble.

TEST=Booted lenovo/x200 with all available CMOS gfx_uma_size settings.

Change-Id: I3f4ceec4224d86113be9bfa3ce4759bed584640d
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/21847
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/src/northbridge/intel/gm45/northbridge.c b/src/northbridge/intel/gm45/northbridge.c
index 3cb7d11..8215979 100644
--- a/src/northbridge/intel/gm45/northbridge.c
+++ b/src/northbridge/intel/gm45/northbridge.c
@@ -71,7 +71,7 @@
 static void mch_domain_read_resources(device_t dev)
 {
 	u64 tom, touud;
-	u32 tomk, tolud, uma_sizek = 0, usable_tomk;
+	u32 tomk, tolud, uma_sizek = 0;
 	u32 pcie_config_base, pcie_config_size;
 
 	/* Total Memory 2GB example:
@@ -130,16 +130,12 @@
 		uma_sizek = gms_sizek + gsm_sizek;
 	}
 
-	usable_tomk = ALIGN_DOWN(tomk, 64 << 10);
-	if (tomk - usable_tomk > (16 << 10))
-		usable_tomk = tomk;
-
-	printk(BIOS_INFO, "Available memory below 4GB: %uM\n", usable_tomk >> 10);
+	printk(BIOS_INFO, "Available memory below 4GB: %uM\n", tomk >> 10);
 
 	/* Report the memory regions */
 	ram_resource(dev, 3, 0, legacy_hole_base_k);
 	ram_resource(dev, 4, legacy_hole_base_k + legacy_hole_size_k,
-		     (usable_tomk - (legacy_hole_base_k + legacy_hole_size_k)));
+		     (tomk - (legacy_hole_base_k + legacy_hole_size_k)));
 
 	/*
 	 * If >= 4GB installed then memory from TOLUD to 4GB