Staging: rtl8192e: Change variable type from u16 to __le16

This patch changes declaration of variable tmp from u16 to
__le16 in order to remove following sparse warning at number
of places:

warning: incorrect type in assignment (different base types)
         expected unsigned short [unsigned] [usertype] tmp
         got restricted __le16 [usertype] <noident>

Signed-off-by: Vaishali Thakkar <vthakkar1994@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>