[media] doc-rst: switch to new names for Full Screen/Aspect keys

We defined better names for keys to activate full screen mode or
change aspect ratio (while keeping the existing keycodes to avoid
breaking userspace), so let's use them in the document.

Signed-off-by: Dmitry Torokhov <[e-mail]>

Documentation/media/uapi/rc/rc-tables.rst

···
 
     -  .. row 78
 
-       -  ``KEY_SCREEN``
+       -  ``KEY_ASPECT_RATIO``
 
        -  Select screen aspect ratio
 
···
 
     -  .. row 79
 
-       -  ``KEY_ZOOM``
+       -  ``KEY_FULL_SCREEN``
 
        -  Put device into zoom/full screen mode