net: dsa: lan9303: Rename lan9303_xxx_packet_processing()

The lan9303_enable_packet_processing, lan9303_disable_packet_processing
functions operate on port, so the names should reflect that.
And to align with lan9303_disable_processing(), rename:

lan9303_enable_packet_processing -> lan9303_enable_processing_port
lan9303_disable_packet_processing -> lan9303_disable_processing_port

Signed-off-by: Egil Hjelmeland <privat@egil-hjelmeland.no>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>