msm: emac: Add handling of ephy RST pin

RST pin should be treated differently from MDIO pins.
Improper toggling of RST pin can cause the spurious
Interrupts storms from ePHY.

Add handling of RST pin in code and add the logic to
Reset ePHY as well.

Change-Id: Ib4c0ee29d8e53c182af1ba8aadd89ef5e4aa21fb
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>