efi_loader: install UEFI System Partition GUID

On the handle for the UEFI System Partition we must install the System
Partition GUID (with a NULL interface).

Let the efidebug command display the GUID.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

cmd/efidebug.c

@@ -16,6 +16,7 @@
 #include <log.h>
 #include <malloc.h>
 #include <mapmem.h>
+#include <part.h>
 #include <search.h>
 #include <linux/ctype.h>
 
@@ -502,6 +503,10 @@ static const struct {
 		"Device-Tree Fixup",
 		EFI_DT_FIXUP_PROTOCOL_GUID,
 	},
+	{
+		"System Partition",
+		PARTITION_SYSTEM_GUID
+	},
 	/* Configuration table GUIDs */
 	{
 		"ACPI table",