luci-app-strongswan-swanctl: remove 15 char section name limit

The 'swanctl.conf' does not impose any length restriction on connection
and children (section) names. They are plain strings parsed by strongswan
config parser without a fixed-size buffer.

Likewise, uci does not enforce a maximum length for named sections.
libuci's uci_validate_str() only restricts the allowed character set
(alphanumeric and underscore, for shell compatibility) and allocates
section names dynamically via strdup(), so there is no built-in
buffer size that would truncate or reject longer names.

The previous 15-character cap therefore had no basis in either
'swanctl.conf' or uci itself and can be dropped without risking
truncation, parsing errors, or incompatibility.

Signed-off-by: Florian Eckert <fe@dev.tdt.de>

applications/luci-app-strongswan-swanctl/htdocs/luci-static/resources/view/strongswan-swanctl/swanctl.js

@@ -44,9 +44,8 @@ function sectionNameCheck(extra_class) {
 			return s['.name'] == v;
 		})) {
 			return _('Remotes, Encryption Proposals and Tunnels may not share the same names.') + ' ' + 
-				_('Use combinations like tunnel1_phase1 that do not exceed 15 characters.');
+				_('Use combinations like tunnel1_phase1.');
 		}
-		if (v.length > 15) return _('Name length shall not exceed 15 characters');
 		return true;
 	}, 'blur', 'keyup');
 	return el;