sched: make use of precise accounting for /proc task stats
sched: make use of precise accounting for /proc task stats

make use of CFS's precise accounting to drive /proc/<pid>/stat statistics.

this code was co-authored by:

 Balbir Singh <balbir@linux.vnet.ibm.com>
 Dmitry Adamushko <e662e14f6c703a049579d1bead8e040b40a3d5b5@gmail.com>
 Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@elte.hu>

Signed-off-by: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@elte.hu>
Signed-off-by: Dmitry Adamushko <e662e14f6c703a049579d1bead8e040b40a3d5b5@gmail.com>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs