util/intelp2m: Add support for Emmitsburg macro generation

Test: Generated GPIO for ASRock Rack SPC741D8-2L2T/BCM.

Change-Id: Ib7ded47fb1c0b87ebb3cecaf3e41319ac552b797
Signed-off-by: Fabian Meyer <fabian.meyer@student.kit.edu>
Co-authored-by: Yussuf Khalil <yussuf.khalil@kit.edu>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/82204
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Maxim <max.senia.poliak@gmail.com>

util/intelp2m/main.go

@@ -73,7 +73,8 @@ func main() {
 		"\ttgl - TigerLake-H SoC\n"+
 		"\tadl - AlderLake PCH\n"+
 		"\tjsl - Jasper Lake SoC\n"+
-		"\tmtl - MeteorLake SoC\n")
+		"\tmtl - MeteorLake SoC\n"+
+		"\tebg - Emmitsburg PCH with Xeon SP\n")
 
 	fieldstyle :=  flag.String("fld", "none", "set fields macros style:\n"+
 		"\tcb  - use coreboot style for bit fields macros\n"+