nimble/controller: Conditionally enable BLE_LL_ISO_BROADCASTER

Enable BLE_LL_ISO_BROADCASTER if BLE_ISO_BROADCAST_SOURCE and/or
BLE_ISO_BROADCAST_SINK is enabled.

Signed-off-by: Mariusz Skamra <mariusz.skamra@codecoup.pl>
diff --git a/nimble/controller/syscfg.yml b/nimble/controller/syscfg.yml
index 19fae47..8a32e2e 100644
--- a/nimble/controller/syscfg.yml
+++ b/nimble/controller/syscfg.yml
@@ -483,8 +483,9 @@
             Enable support for Isochronous Broadcasting state.
         restrictions:
             - BLE_LL_ISO if 1
-        value: MYNEWT_VAL(BLE_ISO_BROADCAST_SOURCE)
+        value: 0
         state: experimental
+
     BLE_LL_ISO_HCI_FEEDBACK_INTERVAL_MS:
         description: >
             Enables ISO synchronization feedback using vendor-specific HCI event.
@@ -613,6 +614,9 @@
     BLE_HW_WHITELIST_ENABLE: 0
     BLE_LL_SCAN_AUX_SEGMENT_CNT: 8
 
+syscfg.vals.'BLE_ISO_BROADCAST_SOURCE || BLE_ISO_BROADCAST_SINK':
+    BLE_LL_ISO_BROADCASTER: 1
+
 syscfg.vals.BLE_LL_ISO_BROADCASTER:
     BLE_LL_CFG_FEAT_LE_ENCRYPTION: 1
     BLE_LL_STACK_SIZE: 180