staging: rtl8192e: Remove variable ieee->short_slot

ieee->short_slot also named priv->rtllib->short_slot is initialized to 1
and then unchanged. All evaluations will result accordingly. Remove
resulting dead code.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/74fe53ccfafe2e0e18319b5502ed83544cc3ffd8.1687583718.git.philipp.g.hortmann@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>