3430ES2 clock: separate 3430ES1/3430ES2 rates in clock code

3430ES2 clock: separate 3430ES1/3430ES2 rates in clock code

On the OMAP3430 architecture, some DPLL3 rates are only available on
3430ES2.  We wish to avoid inadvertently selecting these on 3430ES1.
So we need some way to mark these rates as being 3430ES2-only.  To do
so, add new rate flag RATE_IN_3430ES2, to be used for rates that only
exist on 3430ES2.  (I'm not aware of any 3430ES1-only rates, so, no
corresponding 3430ES1 flag is currently defined.)  RATE_IN_343X is
still present and used for rates which exist on all 343X-level
devices.  The current code assumes that production rates will be
identical to 3430ES2 rates, but this is easy enough to change if
necessary.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>