Staging: wlan-ng: Remove function hfa384x_drvr_commtallies

The function hfa384x_drvr_commtallies is not used anywhere in the kernel
so remove it. Also remove its prototype from the header file.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>