staging: updated Zcache and Zram with LZO/SNAPPY/LZ4 algoritm selection

Conflicts:

	drivers/cpufreq/Kconfig
	drivers/staging/Kconfig
	drivers/staging/Makefile
	drivers/staging/snappy/csnappy.h
	drivers/staging/snappy/csnappy_compress.c
	drivers/staging/snappy/csnappy_decompress.c
	drivers/staging/snappy/csnappy_internal.h
	drivers/staging/zram/zram_drv.c
	drivers/staging/zram/zram_drv.h
	drivers/staging/zram/zram_sysfs.c
fix drivers/staging/zram/zram_drv.c