staging: rtl8712: Removes the FSF mailing address.

This patch fixes the checkpatch issue by removing the Free Software
Foundation's mailing address from the sample GPL notice. Because the FSF
has changed address in the past, and may change again. Linux already
includes a copy of the GPL.

Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>