net: phy: microchip_t1s: fix reset complete status handling

As per the datasheet DS-LAN8670-1-2-60001573C.pdf, the Reset Complete
status bit in the STS2 register has to be checked before proceeding to
the initial configuration. Reading STS2 register will also clear the
Reset Complete interrupt which is non-maskable.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@microchip.com>
Reviewed-by: Ramón Nordin Rodriguez <ramon.nordin.rodriguez@ferroamp.se>
Tested-by: Ramón Nordin Rodriguez <ramon.nordin.rodriguez@ferroamp.se>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>