ARM: OMAP3: Enable workaround for ARM errata 454179, 430973, 621766

Enable the OMAP3 specific errata code for 454179, 430973, 621766
and while at it, remove legacy non-revision checked errata logic.

Signed-off-by: Nishanth Menon <nm@ti.com>
Tested-by: Matt Porter <mporter@konsulko.com>
Reviewed-by: Tom Rini <trini@konsulko.com>