mm: Add Dynamic management of dirty page writeback

Conflicts:
	mm/Kconfig
Async I/O latency to a ssd greatly increased, 34% gain (Creds: kleikamp)
Optimized SLUB memory allocator (creds: Christopher83)
cpufreq: add SmartMax Governor

Conflicts:
	drivers/cpufreq/Makefile
	include/linux/cpufreq.h

Conflicts:
	arch/arm/configs/d802-custom_defconfig

Conflicts:
	arch/arm/configs/d802-custom_defconfig
	drivers/cpufreq/Kconfig
	drivers/cpufreq/Makefile
	include/linux/cpufreq.h