doc/README.gpt: reflow partition type GUID table

The previous patch made the table look bad. Fix it, and leave some
space for a future element being a bit longer than the current
maximum.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
diff --git a/doc/README.gpt b/doc/README.gpt
index 9e0d222..ac975f6 100644
--- a/doc/README.gpt
+++ b/doc/README.gpt
@@ -251,22 +251,22 @@
 	type=0FC63DAF-8483-4772-8E79-3D69D8477DE4;"
 
 Some strings can be also used at the place of known GUID :
-	"system" = PARTITION_SYSTEM_GUID
-	           (C12A7328-F81F-11D2-BA4B-00A0C93EC93B)
-	"mbr"    = LEGACY_MBR_PARTITION_GUID
-	           (024DEE41-33E7-11D3-9D69-0008C781F39F)
-	"msft"   = PARTITION_MSFT_RESERVED_GUID
-	           (E3C9E316-0B5C-4DB8-817D-F92DF00215AE)
-	"data"   = PARTITION_BASIC_DATA_GUID
-	            (EBD0A0A2-B9E5-4433-87C0-68B6B72699C7)
-	"linux"  = PARTITION_LINUX_FILE_SYSTEM_DATA_GUID
-	           (0FC63DAF-8483-4772-8E79-3D69D8477DE4)
-	"raid"   = PARTITION_LINUX_RAID_GUID
-	           (A19D880F-05FC-4D3B-A006-743F0F84911E)
-	"swap"   = PARTITION_LINUX_SWAP_GUID
-	           (0657FD6D-A4AB-43C4-84E5-0933C84B4F4F)
-	"lvm"    = PARTITION_LINUX_LVM_GUID
-	           (E6D6D379-F507-44C2-A23C-238F2A3DF928)
+	"system"          = PARTITION_SYSTEM_GUID
+	                    (C12A7328-F81F-11D2-BA4B-00A0C93EC93B)
+	"mbr"             = LEGACY_MBR_PARTITION_GUID
+	                    (024DEE41-33E7-11D3-9D69-0008C781F39F)
+	"msft"            = PARTITION_MSFT_RESERVED_GUID
+	                    (E3C9E316-0B5C-4DB8-817D-F92DF00215AE)
+	"data"            = PARTITION_BASIC_DATA_GUID
+	                     (EBD0A0A2-B9E5-4433-87C0-68B6B72699C7)
+	"linux"           = PARTITION_LINUX_FILE_SYSTEM_DATA_GUID
+	                    (0FC63DAF-8483-4772-8E79-3D69D8477DE4)
+	"raid"            = PARTITION_LINUX_RAID_GUID
+	                    (A19D880F-05FC-4D3B-A006-743F0F84911E)
+	"swap"            = PARTITION_LINUX_SWAP_GUID
+	                    (0657FD6D-A4AB-43C4-84E5-0933C84B4F4F)
+	"lvm"             = PARTITION_LINUX_LVM_GUID
+	                    (E6D6D379-F507-44C2-A23C-238F2A3DF928)
 	"u-boot-env"      = PARTITION_U_BOOT_ENVIRONMENT
 	                    (3DE21764-95BD-54BD-A5C3-4ABE786F38A8)