[media] docs: fix typo in lirc_device_interface.xml

Reported-by: Daniel Burr <[e-mail]>
Signed-off-by: Jarod Wilson <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

Documentation/DocBook/v4l/lirc_device_interface.xml

···
 <para>The data written to the chardev is a pulse/space sequence of integer
 values. Pulses and spaces are only marked implicitly by their position. The
 data must start and end with a pulse, therefore, the data must always include
-an unevent number of samples. The write function must block until the data has
+an uneven number of samples. The write function must block until the data has
 been transmitted by the hardware.</para>
 </section>