samples: Bluetooth: TMAP periph: Handle empty URI string

The supported URI list may be empty which the sample did not
properly support.

Signed-off-by: Emil Gydesen <emil.gydesen@nordicsemi.no>

samples/bluetooth/tmap_peripheral/src/ccp_call_ctrl.c

@@ -7,6 +7,7 @@
  *
  *  SPDX-License-Identifier: Apache-2.0
  */
+#include <errno.h>
 
 #include <zephyr/kernel.h>
 #include <zephyr/sys/printk.h>
@@ -139,6 +140,12 @@ int ccp_originate_call(void)
 	int err;
 	char uri[CONFIG_BT_TBS_MAX_URI_LENGTH];
 
+	/* If remote_uri is empty then we cannot place a call */
+	if (remote_uri[0] == '\0') {
+		printk("Remote does not support any URI schemes, cannot place call\n");
+		return -ENOENT;
+	}
+
 	strcpy(uri, remote_uri);
 	strcat(uri, URI_SEPARATOR);
 	strcat(uri, CALLER_ID);

samples/bluetooth/tmap_peripheral/src/main.c

@@ -289,9 +289,10 @@ int main(void)
 		err = ccp_originate_call();
 		if (err != 0) {
 			printk("Error sending call originate command!\n");
+		} else {
+			/* Start timer to send terminate call command */
+			k_work_schedule(&call_terminate_set_work, K_MSEC(2000));
 		}
-		/* Start timer to send terminate call command */
-		k_work_schedule(&call_terminate_set_work, K_MSEC(2000));
 	}
 
 	if (peer_is_ums) {