staging: mt7621-pci-phy: add quirks for 'E2' revision using 'soc_device_attribute'

Depending on revision of the chip, 'mt7621_bypass_pipe_rst' function
must be executed. Add better support for this using 'soc_device_match'
in driver probe function.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>