x86: acpi: Fix calculation of DSDT length

Currently, the calculation for the length of the DSDT table includes any
bytes that are added for alignment, but those bytes are not initialized.

This is because the DSDT length is calculated after a call to
acpi_inc_align(). Split this up into the following sequence:

  * acpi_inc()
  * Calculate DSDT length
  * acpi_align()
Signed-off-by: NWolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>

arch/x86/lib/acpi_table.c

@@ -427,7 +427,7 @@ ulong write_acpi_tables(ulong start_addr)
 	       (char *)&AmlCode + sizeof(struct acpi_table_header),
 	       dsdt->length - sizeof(struct acpi_table_header));
 
-	acpi_inc_align(ctx, dsdt->length - sizeof(struct acpi_table_header));
+	acpi_inc(ctx, dsdt->length - sizeof(struct acpi_table_header));
 
 	/* Pack GNVS into the ACPI table area */
 	for (i = 0; i < dsdt->length; i++) {
@@ -450,6 +450,8 @@ ulong write_acpi_tables(ulong start_addr)
 	dsdt->checksum = 0;
 	dsdt->checksum = table_compute_checksum((void *)dsdt, dsdt->length);
 
+	acpi_align(ctx);
+
 	/*
 	 * Fill in platform-specific global NVS variables. If this fails we
 	 * cannot return the error but this should only happen while debugging.