Ext4's typical GPT partition type not recognized

Adding additional entries to the efi conversion array will help prevent
the overwriting of the GPTs of disks with in-use file systems in more
cases. Most notably, this adds partition type 8300 "Linux filesystem"
(0FC63DAF-8483-4772-8E79-3D69D8477DE4), which is often used for ext4 and
btrfs, among others.

This commit itself does nothing to address the underlying problematic
behavior that check_slice() isn't called on partitions of an
unrecognized type, even when they contain a currently mounted file
system.

The additional entries were derived from these two resources:
https://en.wikipedia.org/wiki/GUID_Partition_Table
http://sourceforge.net/p/gptfdisk/code/ci/master/tree/parttypes.cc

Signed-off-by: ilovezfs <ilovezfs@icloud.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4016