Add Realtek linux driver for rtl8192u as provided by Realtek

rtl8192u_linux_2.6.0006.1031.2008.tar.gz, send to me C/C staging ML.

This version won't compile against upstream, doesn't follow
Linux CodingStyle and has their own ieee80211 stack.

Signed-off-by: Mauro Carvalho Chehab
Signed-off-by: Greg Kroah-Hartman