staging: mt7621-pci: delete no more needed 'mt7621_reset_port'

After review all the resets at the beggining the function
'mt7621_reset_port' is not needed anymore. Hence delete it
and its uses.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20200313200913.24321-7-sergio.paracuellos@gmail.com


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