drivers/net/wireless/ath/ath6kl: remove depends on CONFIG_EXPERIMENTAL

The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Kalle Valo <kvalo@qca.qualcomm.com>
Acked-by: John W. Linville <linville@tuxdriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>