staging: rtl8188eu: add spaces around operators in header files

Add spaces around operators in the header files to improve readability
and clear checkpatch issues.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20200719114045.13595-1-straube.linux@gmail.com


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