staging: r8188eu: simplify multiplication in core/rtw_ioctl_set.c

Simplify multiplication in core/rtw_ioctl_set.c. to improve readability
and clear a checkpatch issue.

CHECK: spaces preferred around that '/' (ctx:VxV)

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20210816155818.24005-8-straube.linux@gmail.com


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