ARM: OMAP3EVM: Adding USB internal LDOs board file

EHCI PHY requires these regulators:
        EVM Rev >=E  --> VAUX2
        EVM Rev < E  --> VUSB1V5, VUSB1V8

Adding USB internal LDOs (vusb1v5 & vusb1v8) and VAUX2 to omap3evm
board file. Also removing vaux2_{1/2/3} supplies as they are not
used on omap3 evm.

But we need not to add vaux2 in twl4030_platform_data since it will
be added conditionally.

Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Zumeng Chen <zumeng.chen@windriver.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>