staging: rtl8723bs: os_dep: Cleanup pointer casting code style

Cleanup by adding a space between type and pointer, in accordance with
checkpatch.pl message "(foo*)" should be "(foo *)".

Signed-off-by: Yu Jian Wu <yujian.wu1@gmail.com>
Link: https://lore.kernel.org/r/20200502004747.GA16480@amber


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