staging: rtl8192u: Add or remove spaces to fix style issues

This patch fixes the file r8190_rtl8256.c to avoid the following
checkpatch.pl warnings:
	CHECK: spaces preferred around that '<<' (ctx:VxV)
	CHECK: spaces preferred around that '-' (ctx:VxV)
	CHECK: No space is necessary after a cast

Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com>
Link: https://lore.kernel.org/r/20190826180909.27775-1-sylphrenadin@gmail.com


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