Revert "nohz: Fix another inconsistency between CONFIG_NO_HZ=n and nohz=off"

This reverts commit 3f8f4ae48f4023e1c53722b1dc1a7ab897cbca14:
https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=3f8f4ae48f4023e1c53722b1dc1a7ab897cbca14

On CAF branches the following commit removed sleep_length member
from tick_sched struct:
tick-sched: recalculate sleep length each time it is requested
https://www.codeaurora.org/cgit/quic/la/kernel/msm/commit/?h=kk_2.7-stable&id=9feb87d70208e2236d24ef0ac2fa4d0e28e7d335
Squashed update of kernel from 3.4.95 to 3.4.96

Conflicts:
	mm/vmscan.c
Squashed update of kernel from 3.4.96 to 3.4.97
Squashed update of kernel from 3.4.97 to 3.4.98