pcmcia: convert net pcmcia drivers to use new CIS helpers

Use the new CIS helpers in net pcmcia drivers, which allows for
a few code cleanups.

This revision does not remove the phys_addr assignment in
3c589_cs.c -- a bug noted by Komuro <komurojun-mbn@nifty.com>

CC: David S. Miller <davem@davemloft.net>
CC: netdev@vger.kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>