adapter: Don't refresh adv_manager for non-LE devices

btd_adv_manager_refresh is called upon MGMT_SETTING_DISCOVERABLE setting change but as only LE adapters have an adv_manager, this leads to segmentation fault for non-LE devices:

0 btd_adv_manager_refresh (manager=0x0) at src/advertising.c:1176 1 0x0000556fe45fcb02 in settings_changed (settings=<optimized out>,

    adapter=0x556fe53f7c70) at src/adapter.c:543
2  new_settings_callback (index=<optimized out>, length=<optimized out>,
    param=<optimized out>, user_data=0x556fe53f7c70) at src/adapter.c:573

3 0x0000556fe462c278 in request_complete (mgmt=mgmt@entry=0x556fe53f20c0,
status=<optimized out>, opcode=opcode@entry=7, index=index@entry=0, length=length@entry=4, param=0x556fe53eb5f9) at src/shared/mgmt.c:261
4 0x0000556fe462cd9d in can_read_data (io=<optimized out>,

    user_data=0x556fe53f20c0) at src/shared/mgmt.c:353

5 0x0000556fe46396e3 in watch_callback (channel=<optimized out>,
cond=<optimized out>, user_data=<optimized out>)
at src/shared/io-glib.c:170
6 0x00007fe351c980e5 in g_main_context_dispatch ()
from /usr/lib64/libglib-2.0.so.0

7  0x00007fe351c984b0 in ?? () from /usr/lib64/libglib-2.0.so.0
8  0x00007fe351c987c2 in g_main_loop_run () from /usr/lib64/libglib-2.0.so.0
9  0x0000556fe45abc75 in main (argc=<optimized out>, argv=<optimized out>)
    at src/main.c:770

This commit prevents the call to btd_adv_manager_refresh for non-LE devices.

---
 src/adapter.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

src/adapter.c +2 -2

index 6b9222bcf..daccfdc19 100644
@@ -540,7 +540,8 @@ static void settings_changed(struct btd_adapter *adapter, uint32_t settings)
                g_dbus_emit_property_changed(dbus_conn, adapter->path,
                                        ADAPTER_INTERFACE, "Discoverable");
                store_adapter_info(adapter);
-               btd_adv_manager_refresh(adapter->adv_manager);
+               if (adapter->supported_settings & MGMT_SETTING_LE)
+                       btd_adv_manager_refresh(adapter->adv_manager);
        }
 
        if (changed_mask & MGMT_SETTING_BONDABLE) {
--

2.16.2