platform/chrome: cros_ec_typec: Configure muxes at start of port update

There are situations where the mux state reported by the Embedded
Controller (EC), might lag the partner "connected" state. So, the mux
state might still suggest that a partner is connected, while the PD
"connected" state, being in Try.SNK (for example) suggests that the
partner is disconnected.

In such a scenario, we will end up sending a disconnect command to the
mux driver, followed by a connect command, since the mux is configured
later. Avoid this by configuring the mux before
registering/disconnecting a partner.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Link: https://lore.kernel.org/chrome-platform/20220208184721.1697194-4-pmalani@chromium.org/