arm-soc: cleanups

A large number of cleanups, all over the platforms. This is dominated
largely by the Samsung platforms (s3c, s5p, exynos) and a few of the
others moving code out of arch/arm into more appropriate subsystems.
The clocksource and irqchip drivers are now abstracted to the point
where platforms that are already cleaned up do not need to even specify
the driver they use, it can all get configured from the device tree
as we do for normal device drivers. The clocksource changes basically
touch every single platform in the process.

We further clean up the use of platform specific header files here,
with the goal of turning more of the platforms over to being
"multiplatform" enabled, which implies that they cannot expose
their headers to architecture independent code any more.

It is expected that no functional changes are part of the cleanup.
The overall reduction in total code lines is mostly the result of
removing broken and obsolete code.
Merge tag 'cleanup_for_v3.9_round3' of git://git.infradead.org/users/jcooper/linux into next/cleanup

mvebu cleanup vor v3.9 round3

 - fix typo in mvebu clokc gating documentation.

* tag 'cleanup_for_v3.9_round3' of git://git.infradead.org/users/jcooper/linux:
  ARM: mvebu: correct gated clock documentation