ARM: OMAP: Remove unnecessary omap2_globals.

This patch removes unnecessary omap2_globals and pass the global structures
directly as function argument.

The proposed cleanup was suggested by Russell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>