[nrf fromtree] Bluetooth: Host: Disable bt_hci_cmd_send_sync workaround

The workaround in bt_cmd_send_sync should no longer by needed when
tx_processor is not on the system work queue.

Signed-off-by: Aleksander Wasaznik <[email protected]>
(cherry picked from commit 04b8dba)
Signed-off-by: Kyra Lengfeld <[email protected]>

Author: alwa-nordic

subsys/bluetooth/host/hci_core.c

@@ -472,10 +472,11 @@ int bt_hci_cmd_send_sync(uint16_t opcode, struct net_buf *buf,
 
 	/* TODO: disallow sending sync commands from syswq altogether */
 
-	/* Since the commands are now processed in the syswq, we cannot suspend
-	 * and wait. We have to send the command from the current context.
+	/* If the commands are processed in the syswq and we are on the
+	 * syswq, then we cannot suspend and wait. We have to send the
+	 * command from the current context.
 	 */
-	if (k_current_get() == &k_sys_work_q.thread) {
+	if (!IS_ENABLED(CONFIG_BT_TX_PROCESSOR_THREAD) && k_current_get() == &k_sys_work_q.thread) {
 		/* drain the command queue until we get to send the command of interest. */
 		struct net_buf *cmd = NULL;