Allow input system access to /dev/v4l-touchX

Bug: 62940136
Test: read /dev/v4l-touchX from inputflinger

Change-Id: Ifcece4192c567e0cbaba1b7ad40d25c8f34f8e40

private/file_contexts

@@ -167,6 +167,7 @@
 /dev/uio[0-9]*		u:object_r:uio_device:s0
 /dev/urandom		u:object_r:random_device:s0
 /dev/usb_accessory	u:object_r:usbaccessory_device:s0
+/dev/v4l-touch[0-9]*	u:object_r:input_device:s0
 /dev/vcs[0-9a-z]*	u:object_r:vcs_device:s0
 /dev/video[0-9]*	u:object_r:video_device:s0
 /dev/vndbinder		u:object_r:vndbinder_device:s0