staging: r8188eu: Add source files for new driver - part 1

This commit adds core/rtw_ap.c, core/rtw_br_ext.c, and core/rtw_cmd.c

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: lwfinger