lib: uuid: add partition type GUID for extended bootloader

The Extended Boot Loader Partition (XBOOTLDR) is a standard defined by
the Discoverable Partitions Specification (DPS) to host boot loader
resources outside of the EFI System Partition ([1], [2]).

Defining this GUID (bc13c2ff-59e6-4262-a352-b275fd6f7172) allows U-Boot
to correctly identify and label these partitions using the "xbootldr"
shorthand.

[1] https://uapi-group.org/specifications/specs/discoverable_partitions_specification/#extended-boot-loader-partition:~:text=UEFI%20Specification.-,Extended%20Boot%20Loader%20Partition,-bc13c2ff%2D59e6%2D4262
[2] https://uapi-group.org/specifications/specs/boot_loader_specification/
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

doc/README.gpt

@@ -286,6 +286,8 @@ Some strings can be also used at the place of known GUID :
 	                    (E6D6D379-F507-44C2-A23C-238F2A3DF928)
 	"u-boot-env"      = PARTITION_U_BOOT_ENVIRONMENT
 	                    (3DE21764-95BD-54BD-A5C3-4ABE786F38A8)
+	"xbootldr"        = PARTITION_XBOOTLDR
+	                    (BC13C2FF-59E6-4262-A352-B275FD6F7172)
 
     "uuid_disk=...;name=u-boot,size=60MiB,uuid=...;
 	name=kernel,size=60MiB,uuid=...,type=linux;"

include/part_efi.h

@@ -60,6 +60,9 @@
 #define PARTITION_U_BOOT_ENVIRONMENT \
 	EFI_GUID( 0x3de21764, 0x95bd, 0x54bd, \
 		0xa5, 0xc3, 0x4a, 0xbe, 0x78, 0x6f, 0x38, 0xa8)
+#define PARTITION_XBOOTLDR \
+	EFI_GUID( 0xbc13c2ff, 0x59e6, 0x4262, \
+		0xa3, 0x52, 0xb2, 0x75, 0xfd, 0x6f, 0x71, 0x72)
 
 /* Special ChromiumOS things */
 #define PARTITION_CROS_KERNEL \

lib/uuid.c

@@ -86,6 +86,7 @@ static const struct {
 	{"swap",	NULL,	PARTITION_LINUX_SWAP_GUID},
 	{"lvm",		NULL,	PARTITION_LINUX_LVM_GUID},
 	{"u-boot-env",	NULL,	PARTITION_U_BOOT_ENVIRONMENT},
+	{"xbootldr",	NULL,	PARTITION_XBOOTLDR},
 	{"cros-kern",	NULL,	PARTITION_CROS_KERNEL},
 	{"cros-root",	NULL,	PARTITION_CROS_ROOT},
 	{"cros-fw",	NULL,	PARTITION_CROS_FIRMWARE},