ARM: OMAP2xxx: hwmod data: share common hwmods between OMAP2420 and OMAP2430

After the link registration conversion, it's much easier to share some
hwmod data between OMAP2420 and 2430.  Move the shareable data into a
common file.  This should save some memory and lines of source, at the
cost of readability.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Benoît Cousson <b-cousson@ti.com>