ARM: OMAP2+: omap_device: remove obsolete pm_lats and early_device code

Remove now-obsolete code from arch/arm/mach-omap2/omap_device.c.  This
mostly consists of removing the first attempt at device PM latency
handling.  This was never really used, has been replaced by the common
dev_pm_qos code, and needs to go away as part of the DT conversion.
Also, the early platform_device creation code has been removed, as it
appears to be unused.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>