staging: typec: tcpm: Do not send PING msgs in TCPM

PING messages are used to monitor the connect/disconnect.
However, when PD is carried over CC, so this is not required.

Also, the spec does not clearly say if PD is possible when
Type-c is connected to Type-A/B. So, removing sending
PING messages altogether.

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>