staging: wlan-ng: Replace function hfa384x_dowmem()

staging: wlan-ng: Replace function hfa384x_dowmem()

Remove parameters mode, cmdcb, usercb, and usercb_data from
hfa384x_dowmem as these parameters are only assigned the same constant
values (DOWAIT, NULL, NULL, NULL respectively).
Modify hfa384x_dowmem to use these constants directly. Remove check for
value of mode (as it will always be DOWAIT).
Remove function hfa384x_dowmem_wait as it does nothing except call
hfa384x_dowmem with these extra arguments.
Modify call sites of hfa384x_dowmem_wait to call hfa384x_dowmem instead.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Link: https://lore.kernel.org/r/20190712062807.9361-10-nishkadg.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>