staging: rtl8192u: r8192U_core: fix space before close parenthesis code style error

A space existed before the close parenthesis of an if statement. This patch
removes it to follow the kernel code style.

Signed-off-by: Raphaël Beamonte <raphael.beamonte@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>