Staging: rt2860: includecheck fix: rt_linux.h

fix the following 'make includecheck' warning:

  drivers/staging/rt2860/rt_linux.h: linux/wireless.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/rt2860/rt_linux.h

@@ -63,10 +63,6 @@
 #include <linux/ctype.h>
 #include <linux/vmalloc.h>
 
-
-#ifdef RT30xx
-#include <linux/wireless.h>
-#endif
 #include <net/iw_handler.h>
 
 // load firmware