pcmcia: remove useless msleep in ds.c

As this is the socket thread (pccardd) starting up, we do not have
anything to wait for in ds.c. Instead, wait the same amount of time
in pccardd to allow userspace to catch up and - possibly - execute
pcmcia-socket-startup.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>