ARM: OMAP: Cleanup boot parameters usage

The boot parameters are read from individual variables
assigned for each of them. This been corrected and now
they are stored as a part of the global data 'gd'
structure. So read them from 'gd' instead.

Signed-off-by: Sricharan R <r.sricharan@ti.com>
[trini: Add igep0033 hunk]
Signed-off-by: Tom Rini <trini@ti.com>