part:efi: add GUID for linux file system data

Previously, Linux used the same GUID for the data partitions as Windows
(Basic data partition: EBD0A0A2-B9E5-4433-87C0-68B6B72699C7).
This created problems when dual-booting Linux and Windows in UEFI-GPT
Setup, so a new GUID (Linux filesystem data:
0FC63DAF-8483-4772-8E79-3D69D8477DE4) was defined jointly by GPT fdisk
and GNU Parted developers.

Signed-off-by: Patrick Delaunay <patrick.delaunay73@gmail.com>
diff --git a/doc/README.gpt b/doc/README.gpt
index 59fdeeb..6e298d2 100644
--- a/doc/README.gpt
+++ b/doc/README.gpt
@@ -31,7 +31,8 @@
 separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters
 (32 digits and 4 hyphens)
 
-For instance, GUID of Linux data partition: EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
+For instance, GUID of Basic data partition: EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
+and GUID of Linux filesystem data: 0FC63DAF-8483-4772-8E79-3D69D8477DE4
 
 Historically there are 5 methods to generate this number. The oldest one is
 combining machine's MAC address and timer (epoch) value.