staging: wfx: remove unused included header files

Many header files have been included, but never used. Those header
files have been removed.

Signed-off-by: Muhammad Usama Anjum <musamaanjum@gmail.com>
Link: https://lore.kernel.org/r/20210211143637.GA177425@LEGION
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>