disk: add swap partition ID constants

Add the SwapPartitionGUID for GPT and DosSwapID for DOS.
Register both in the idMap.

Refs:
- https://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/
- https://tldp.org/HOWTO/Partition-Mass-Storage-Definitions-Naming-HOWTO/x190.html

pkg/disk/disk.go

@@ -56,6 +56,8 @@ const (
 
 	RootPartitionUUID = "6264D520-3FB9-423F-8AB8-7A0A8E3D3562"
 
+	SwapPartitionGUID = "0657FD6D-A4AB-43C4-84E5-0933C84B4F4F"
+
 	// Extended Boot Loader Partition
 	XBootLDRPartitionGUID = "BC13C2FF-59E6-4262-A352-B275FD6F7172"
 
@@ -70,6 +72,9 @@ const (
 
 	// Partition type ID for ESP on dos
 	DosESPID = "ef00"
+
+	// Partition type ID for swap
+	DosSwapID = "82"
 )
 
 // pt type -> type -> ID mapping for convenience
@@ -80,13 +85,15 @@ var idMap = map[PartitionTableType]map[string]string{
 		"data": DosLinuxTypeID,
 		"esp":  DosESPID,
 		"lvm":  DosLinuxTypeID,
+		"swap": DosSwapID,
 	},
 	PT_GPT: {
 		"bios": BIOSBootPartitionGUID,
 		"boot": XBootLDRPartitionGUID,
 		"data": FilesystemDataGUID,
 		"esp":  EFISystemPartitionGUID,
 		"lvm":  LVMPartitionGUID,
+		"swap": SwapPartitionGUID,
 	},
 }