xhci: add xhci_address_ctx trace event

This patch defines a new event class, called xhci_log_ctx,
that records in the ring buffer the context data, the
context type (input or output), the context dma and virtual
addresses, the context endpoint entries, the slot ID and
whether the xHC uses 64 byte context data structures.

This information can be used, later, to parse and display
the context data fields with the appropriate plugin using
the trace-cmd tool.

Also, this patch defines a trace event, called xhci_address_ctx,
to trace the contexts related to the Address Device command and
adds the associated tracepoints in xhci_address_device().

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>