staging: rtl8712: fix a foo * bar errors reported by checkpatch

fixes the following error:

drivers/staging/rtl8712/rtl8712_xmit.c:379:  ERROR: "foo * bar" should
be "foo *bar"

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>