link status feature is available on Cisco IOS XR (ASR)

remote.php:
	new breedfunc pointer 'iosxr4-getportstatus-main' => 'iosxr4ReadInterfaceStatus'
deviceconfig.php:
	+ iosxr4ReadInterfaceStatus
fix Live ports tab is blank for some breeds

interface.php: add check for valid breed function in renderPortsInfo