host/audio/pacs: allow ble_svc_audio_pacs_set params to be static const

This allows to params to be static const without any casting.
diff --git a/nimble/host/audio/services/pacs/include/services/pacs/ble_audio_svc_pacs.h b/nimble/host/audio/services/pacs/include/services/pacs/ble_audio_svc_pacs.h
index fdbcbee..9410c7b 100644
--- a/nimble/host/audio/services/pacs/include/services/pacs/ble_audio_svc_pacs.h
+++ b/nimble/host/audio/services/pacs/include/services/pacs/ble_audio_svc_pacs.h
@@ -71,7 +71,7 @@
  * @return                              0 on success;
  *                                      A non-zero value on failure.
  */
-int ble_svc_audio_pacs_set(uint8_t flags, struct ble_svc_audio_pacs_set_param *param);
+int ble_svc_audio_pacs_set(uint8_t flags, const struct ble_svc_audio_pacs_set_param *param);
 
 /**
  * @brief Set available context types.
diff --git a/nimble/host/audio/services/pacs/src/ble_audio_svc_pacs.c b/nimble/host/audio/services/pacs/src/ble_audio_svc_pacs.c
index 92155f4..ef53f94 100644
--- a/nimble/host/audio/services/pacs/src/ble_audio_svc_pacs.c
+++ b/nimble/host/audio/services/pacs/src/ble_audio_svc_pacs.c
@@ -386,7 +386,7 @@
 }
 
 int
-ble_svc_audio_pacs_set(uint8_t flags, struct ble_svc_audio_pacs_set_param *param)
+ble_svc_audio_pacs_set(uint8_t flags, const struct ble_svc_audio_pacs_set_param *param)
 {
     int rc;