pcmcia: ds: Fix function name disparity in header

Fixes the following W=1 kernel build warning(s):

 drivers/pcmcia/ds.c:96: warning: expecting prototype for pcmcia_store_new_id(). Prototype was for new_id_store() instead

Signed-off-by: Lee Jones <lee.jones@linaro.org>
[linux@dominikbrodowski.net: removed list of CCs]
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>