acpi: Change Processor ACPI Name (Intel only)

The ACPI Spec 2.0 states, that Processor declarations should be made
within the ACPI namespace \_SB and not \_PR anymore. \_PR is deprecated
and is removed here for Intel CPUs only.

Tested on:
* X11SSH (Kabylake)
* CFL Platform
* Asus P8Z77-V LX2 and Windows 10

FWTS does not return FAIL anymore on ACPI tests

Tested-by: Angel Pons <th3fanbus@gmail.com>
Change-Id: Ib101ed718f90f9056d2ecbc31b13b749ed1fc438
Signed-off-by: Christian Walter <christian.walter@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37814
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/src/arch/x86/acpigen.c b/src/arch/x86/acpigen.c
index a599b0e..26fe08f 100644
--- a/src/arch/x86/acpigen.c
+++ b/src/arch/x86/acpigen.c
@@ -340,7 +340,7 @@
 void acpigen_write_processor(u8 cpuindex, u32 pblock_addr, u8 pblock_len)
 {
 /*
-	Processor (\_PR.CPcpuindex, cpuindex, pblock_addr, pblock_len)
+	Processor (\_SB.CPcpuindex, cpuindex, pblock_addr, pblock_len)
 	{
 */
 	char pscope[16];
@@ -376,7 +376,7 @@
 {
 	int core_id;
 
-	acpigen_write_method("\\_PR.CNOT", 1);
+	acpigen_write_method("\\_SB.CNOT", 1);
 	for (core_id = 0; core_id < number_of_cores; core_id++) {
 		char buffer[DEVICE_PATH_MAX];
 		snprintf(buffer, sizeof(buffer), CONFIG_ACPI_CPU_STRING,