class, subclass and progif were never used, so don't bother setting
them.
Use the C99 flexible array construct to denote a variable amount of
data rather than the old-school [1] construct. We have required c99
compilers for some time.
Use a switch on ti_chip() to find which SoC we are on. This allow us t
only enable support for the SoCs we are built for.
Decode the arguments passed to _umtx_op().  In particular, decode the
opcode.

MFC after:	1 week
Sponsored by:	Norse
Remove the omap3 directory that should have happened in r273041.
Move the sdhci option to files.ti, it's common to both SoCs.