usb: typec: tcpm: add state machine support for SRC_VDM_IDENTITY_REQUEST

Add SRC_VDM_IDENTITY_REQUEST state which first enters after SRC_STARTUP.
The state sends Discover Identity on SOP' and transitions to
SRC_SEND_CAPABILITIES. SRC_SEND_CAPABILITIES will transition back into
SRC_VDM_IDENTITY_REQUEST instead of retrying immediately.

Signed-off-by: RD Babiera <rdbabiera@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240108191620.987785-23-rdbabiera@google.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>