igd.asl rewrite

Old igd.asl had inconsistent addresses (between _DOD and actual device)
and ghost devices. Any of those is enough to make brightness on windows
fail and make igd.asl out-of-ACPI-spec. Also old code favoured ridiculous
copying of the same thing 6 times per chipset. Leave only hooking up and
chipset-specific part in chipset directory. Move NVS handling and ACPI-spec
parts to a common file.

Change-Id: I556769e5e28b83e7465e3db689e26c8c0ab44757
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/7472
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <edward.ocallaghan@koparo.com>
Reviewed-by: Timothy Pearson <tpearson@raptorengineeringinc.com>

src/northbridge/intel/gm45/gma.c

@@ -491,6 +491,27 @@ static void gma_set_subsystem(device_t dev, unsigned vendor, unsigned device)
 	}
 }
 
+const struct i915_gpu_controller_info *
+intel_gma_get_controller_info(void)
+{
+	device_t dev = dev_find_slot(0, PCI_DEVFN(0x2,0));
+	if (!dev) {
+		return NULL;
+	}
+	struct northbridge_intel_gm45_config *chip = dev->chip_info;
+	return &chip->gfx;
+}
+
+static void gma_ssdt(void)
+{
+	const struct i915_gpu_controller_info *gfx = intel_gma_get_controller_info();
+	if (!gfx) {
+		return;
+	}
+
+	drivers_intel_gma_displays_ssdt_generate(gfx);
+}
+
 static struct pci_operations gma_pci_ops = {
 	.set_subsystem = gma_set_subsystem,
 };
@@ -499,6 +520,7 @@ static struct device_operations gma_func0_ops = {
 	.read_resources = pci_dev_read_resources,
 	.set_resources = pci_dev_set_resources,
 	.enable_resources = pci_dev_enable_resources,
+	.acpi_fill_ssdt_generator = gma_ssdt,
 	.init = gma_func0_init,
 	.scan_bus = 0,
 	.enable = 0,