Delete coin blocker exports from IO DLLs

These never get called at the moment, so we have no way of
guaranteeing that any existing implementations are even correct. If
we do decide to start emulating the coin blocker then we will need
to advance the API versions, which will (hopefully) force any
third-party devs to test their coin blocker code before opting in.

divahook/diva-dll.c

@@ -18,9 +18,6 @@ const struct dll_bind_sym diva_dll_syms[] = {
     }, {
         .sym = "diva_io_jvs_read_coin_counter",
         .off = offsetof(struct diva_dll, jvs_read_coin_counter),
-    }, {
-        .sym = "diva_io_jvs_set_coin_blocker",
-        .off = offsetof(struct diva_dll, jvs_set_coin_blocker),
     }, {
         .sym = "diva_io_slider_init",
         .off = offsetof(struct diva_dll, slider_init),

divahook/diva-dll.h

@@ -9,7 +9,6 @@ struct diva_dll {
     HRESULT (*jvs_init)(void);
     void (*jvs_poll)(uint8_t *opbtn, uint8_t *beams);
     void (*jvs_read_coin_counter)(uint16_t *total);
-    void (*jvs_set_coin_blocker)(bool open);
     HRESULT (*slider_init)(void);
     void (*slider_start)(diva_io_slider_callback_t callback);
     void (*slider_stop)(void);

divahook/divahook.def

@@ -16,7 +16,6 @@ EXPORTS
     diva_io_jvs_init
     diva_io_jvs_poll
     diva_io_jvs_read_coin_counter
-    diva_io_jvs_set_coin_blocker
     diva_io_slider_init
     diva_io_slider_set_leds
     diva_io_slider_start