samples: cellular: modem_shell: link: Error msg for search config read

A better error text made when reading search configuration failed
due to missing search configuration.

Signed-off-by: Tommi Rantanen <tommi.rantanen@nordicsemi.no>

Author: trantanen

include/modem/lte_lc.h

@@ -1783,7 +1783,7 @@ int lte_lc_periodic_search_set(const struct lte_lc_periodic_search_cfg *const cf
  *
  * @retval 0 if a configuration was found and populated to the provided pointer.
  * @retval -EINVAL if input parameter was @c NULL.
- * @retval -ENOENT if no periodic search was not configured.
+ * @retval -ENOENT if periodic search configuration was not set.
  * @retval -EFAULT if an AT command failed.
  * @retval -EBADMSG if the modem responded with an error to an AT command or the
  *         response could not be parsed.

samples/cellular/modem_shell/src/link/link_shell.c

@@ -2169,7 +2169,10 @@ static int link_shell_search(const struct shell *shell, size_t argc, char **argv
 	if (operation == LINK_OPERATION_READ) {
 
 		ret = lte_lc_periodic_search_get(&search_cfg);
-		if (ret) {
+		if (ret == -ENOENT) {
+			mosh_error("Reading search configuration failed: no configuration set");
+			return ret;
+		} else if (ret) {
 			mosh_error("Reading search configuration failed: %d", ret);
 			return ret;
 		}