media: lirc-func.rst: new ioctl LIRC_GET_REC_TIMEOUT is not in a separate file

This fixes the warning:

Documentation/media/uapi/rc/lirc-func.rst:9: WARNING: toctree contains reference to nonexisting document 'media/uapi/rc/lirc-get-rec-timeout'

The ioctl is documented in lirc-set-rec-timeout.
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

Documentation/media/uapi/rc/lirc-func.rst

@@ -17,7 +17,6 @@ LIRC Function Reference
     lirc-get-rec-resolution
     lirc-set-send-duty-cycle
     lirc-get-timeout
-    lirc-get-rec-timeout
     lirc-set-rec-timeout
     lirc-set-rec-carrier
     lirc-set-rec-carrier-range