ABI: sysfs-class-extcon: use uppercase X for wildcards

Uppercase letters X, Y and Z are handled as wildcards by
scripts/get_abi.pl.

We can't do that with lowercase letters, as they're used
everywhere.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/2dfd3f80cea2d0501f6451f2e66000b00fda3346.1632994837.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/ABI/testing/sysfs-class-extcon

@@ -65,19 +65,19 @@ Description:
 		interface associated with each cable cannot update
 		multiple cable states of an extcon device simultaneously.
 
-What:		/sys/class/extcon/.../cable.x/name
+What:		/sys/class/extcon/.../cable.X/name
 Date:		February 2012
 Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 Description:
-		The /sys/class/extcon/.../cable.x/name shows the name of cable
-		"x" (integer between 0 and 31) of an extcon device.
+		The /sys/class/extcon/.../cable.X/name shows the name of cable
+		"X" (integer between 0 and 31) of an extcon device.
 
-What:		/sys/class/extcon/.../cable.x/state
+What:		/sys/class/extcon/.../cable.X/state
 Date:		February 2012
 Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 Description:
-		The /sys/class/extcon/.../cable.x/state shows and stores the
-		state of cable "x" (integer between 0 and 31) of an extcon
+		The /sys/class/extcon/.../cable.X/state shows and stores the
+		state of cable "X" (integer between 0 and 31) of an extcon
 		device. The state value is either 0 (detached) or 1
 		(attached).