Revert "mm: optimize Kernel Samepage Merging(KSM)"

This reverts commit 96ff7d94bf4ca506325c9123c4dbd359896d3e52.
Revert "UKSM: Upgrade to 0.1.2.2"

This reverts commit 3c25d4d64aa8d63e9e054f0db6d90aa3c03c0e34.