soc: fsl: guts: drop platform driver

This driver cannot be unloaded and it will be needed very early in the
boot process because other driver (weakly) depend on it (eg. for chip
errata handling). Drop all the platform driver and devres stuff and
simply make it a core_initcall.

Signed-off-by: Michael Walle <michael@walle.cc>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>