trusty: libtrusty: Add vsock support

Add support for connecting to a vsock port that multiplexes trusty
services. The first vsock packet contains the tipc port name. To enable
this mode, pass "VSOCK:<cid>:<port>" as the device name string (where
<cid> and <port> is replaced with the cid and port numbers you want to
connect to).

Test: manual - ran storageproxyd and storage test with new option
Bug: 298705967
Change-Id: I9b75244ca38b7eb69ed7fc19b27aa309d0f7ed13