staging: typec: tcpm: Follow Try.SRC exit requirements

According to spec:
" 4.5.2.2.9.2 Exiting from Try.SRC State:
The port shall transition to Attached.SRC when the SRC.Rd
state is detected on exactly one of the CC1 or CC2 pins for
at least tPDDebounce. The port shall transition to
TryWait.SNK after tDRPTry and the SRC.Rd state has not been
detected."

Signed-off-by: Badhri Jagan Sridharan <Badhri@google.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>