OMAP2/3: Add omap_type() for determining GP/EMU/HS

The omap_type() function is added and returns the DEVICETYPE field of
the CONTROL_STATUS register.  The result can be used for conditional
code based on whether device is GP (general purpose), EMU or
HS (high security). Also move the type defines so omap1 code
compile does not require ifdefs for sections using these defines.

This code is needed for the following fix to set the SRAM
size correctly for HS omaps.  Also at least PM and watchdog
code will need this function.

Signed-off-by: Kevin Hilman <khilman@ti.deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>