Staging: rtl8723au: core: Fix "foo * bar" warning.

This patch fixes these error messages found by checkpatch.pl:
ERROR: "foo* bar" should be "foo *bar"

Signed-off-by: Aybuke Ozdemir <aybuke.147@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>