Allow up to four cards (only use the first slot for now).
* src/slots.c (MAX_SLOTS): New. (scute_slots_initialize): Allocate slots of MAX_SLOTS. (slots_update_slot): Don't try to detect new card. (slots_detect_slot): New. (slots_update_all): Call slots_detect_slot to detect new card.
This commit breaks t-getslotinfo test.
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>