[PATCH] ARM: OMAP: OMAP2 CPU identification

[PATCH] ARM: OMAP: OMAP2 CPU identification

I put together this basic OMAP2 identification code, since I would need
to distinguish between 2410 and 2420.

The second patch makes an attempt to fix up places where
cpu_is_omap2420() is used, replacing them with the newly introduced more
type specific macros. These are based on comments in the code.