ACPI: Refactor use of global and device NVS

After ChromeOS NVS was moved to a separate allocation and the use
of multiple OperationRegions, maintaining the fixed offsets is not
necessary.

Use actual structure size for OperationRegions, but align the
allocations to 8 bytes or sizeof(uint64_t).

Change-Id: I9c73b7c44d234af42c571b23187b924ca2c3894a
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51639
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/vendorcode/google/chromeos/gnvs.h

@@ -8,8 +8,6 @@
 #define ACTIVE_ECFW_RO		0
 #define ACTIVE_ECFW_RW		1
 
-#define GNVS_DEVICE_NVS_OFFSET 0x1000
-
 struct chromeos_acpi {
 	/* ChromeOS specific */
 	u32	vbt0;		// 00 boot reason