X11: add comments to X config

etc/X11/xorg_seat1.conf

 Section "Device"
 	Identifier	"Seat1"
 	Driver		"radeon"
-	BusID		"PCI:01:0:0"
+	BusID		"PCI:01:0:0" # decimal instead of hexadeci from lspci
+	# 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Caicos [Radeon HD 6450/7450/8450 / R5 230 OEM]
 EndSection
 
+# ignore all input devices
 Section "InputClass"
 	Identifier	"ignore_other_seats"
 	Option		"Ignore"	"yes"
 EndSection
 
+# do not ignore input devices tagged by udev for this seat
 Section "InputClass"
 	Identifier	"use_seat_devices"
 	MatchTag	"input_seat1"
 	Option		"Ignore"	"no"
 EndSection
 
+# disallow vt switching and ignore other GPUs
 Section "ServerFlags"
 	Option		"AutoAddGPU"	"FALSE"
 	Option "DontVTSwitch" "on"

etc/X11/xorg_seat2.conf

 Section "Device"
 	Identifier	"Seat2"
 	Driver		"radeon"
-	BusID		"PCI:16:0:0"
+	BusID		"PCI:16:0:0" # decimal instead of hexadeci from lspci
+	# 10:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Caicos [Radeon HD 6450/7450/8450 / R5 230 OEM]
 EndSection
 
+# ignore all input devices
 Section "InputClass"
 	Identifier	"ignore_other_seats"
 	Option		"Ignore"	"yes"
 EndSection
 
+# do not ignore input devices tagged by udev for this seat
 Section "InputClass"
 	Identifier	"use_seat_devices"
 	MatchTag	"input_seat2"
 	Option		"Ignore"	"no"
 EndSection
 
+# disallow vt switching and ignore other GPUs
 Section "ServerFlags"
 	Option		"AutoAddGPU"	"FALSE"
 	Option "DontVTSwitch" "on"