net: stmmac: boot up KPI changes

Read early ethernet dtsi flag to enable this feature.
Disable autoneg and configure MAC and PHY with 100 Mbps
link speed.
Read MAC addr, IPv4 and IPv6 addresses from kernel cmd
line parameters in order to assign these to ethernet
interface.

Change-Id: Ibeeebb73b4cbbd0950a1bff065297c4e58be671d
Acked-by: Nagarjuna Chaganti <nchagant@qti.qualcomm.com>
Signed-off-by: Suraj Jaiswal <jsuraj@codeaurora.org>