net: phy: bugfixes: mv88E61xx multichip addressing support

With these fixes, this driver works properly for multi chip
addressging mode

Bugfixes:
1. Build error fixed for function mv88e61xx_busychk_multic-fixed
2. PHY dev address error detection- fixed
3. wrong busy bit was refered in function mv88e61xx_busychk -fixed
4. invalid data read ptr was refered for RD_PHY in case of
	multichip addressing mode -fixed

The Multichip Address mode is tested with RD6281A board having
MV88E6165 switch on it

Signed-off-by: Prafulla Wadaskar <prafulla@marvell.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>