sfdisk: extend --part-type, support aliases

sfdisk: extend --part-type, support aliases

* add support for aliases to sfdisk scripts
* add shortcuts and aliases to --part-type command

Note that --part-type evaluates shortcuts and aliases as the last
possibility (so after regular type string). This is necessary for
backward compatibility.

Example ('raid' type alias):
 # sfdisk --part-type /dev/sdc 1 raid

 # fdisk -l /dev/sdc
 ...
 Device     Boot Start    End Sectors Size Id Type
 /dev/sdc1        2048 204799  202752  99M fd Linux raid autodetect

Example ('L' type shortcut):

 # sfdisk --part-type /dev/sdc 1 L

 # fdisk -l /dev/sdc
 ...
 Device     Boot Start    End Sectors Size Id Type
 /dev/sdc1        2048 204799  202752  99M 83 Linux

Addresses: https://github.com/karelzak/util-linux/issues/958
Signed-off-by: Karel Zak <kzak@redhat.com>