Varnish: sync mobile UA redirects with squid

Sync our mobile UA list for mobile redirects with what we have in squid.
This adds "semc-browser" and "vodafone", as well as fixing the case
sensitive match for ^(lge?|sie|nec|sgh|pg).

Change-Id: Ie9b4070037c90694a85e1f17276837ba90beccab