Revert "ARM: Tegra:mpdecision : use nr_cpu_ids isntead of NR_CPUS"

This reverts commit cf2b351c6a63fd2d95d740b0a188a87c34737845.
Revert "ksm: check and skip page, if it is already scanned"

This reverts commit a6beb83e463b455a6c07bcec98bd88c1aad0a97b.