Merge tag 'kconfig-cleanup-for-3.15' into imx/soc

- Remove common kconfig options required by multi-platform builds out
of individual platforms as they are redundant.
- Make SMP, CACHE_L2X0 and GPIO config options user visible on
multi-platform builds as most platforms enable these options and all
platforms can run with them enabled.
- Make multi-platform v6 default to more optimal v6k rather than v6
- Remove the last bit of mach-virt and convert it to just a kconfig
option.

Conflicts:
	arch/arm/mach-omap2/Kconfig