ksm: Provide support to use deferred timers for scanner thread

KSM thread to scan pages is getting schedule on definite timeout.
That wakes up CPU from idle state and hence may affect the power
consumption. Provide an optional support to use deferred timer
which suites low-power use-cases.

To enable deferred timers,
$ echo 1 > /sys/kernel/mm/ksm/deferred_timer

Change-Id: I07fe199f97fe1f72f9a9e1b0b757a3ac533719e8
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Revert "Fix Documentation"

This reverts commit a2ee9a7d283aac0177b83c66ef2696ece31ed632.
Revert "Same as before"

This reverts commit ca3a61dbe187e8f37ed566f1ff91aa3e7a94d016.
Revert "Update MSM_Thermal properly (copying @faux123)"

This reverts commit b37c3f89112eb3c8b116f192eedf36c900c2a85d.
Revert "Fix another file"

This reverts commit be8cc5ae0aaf197e92b549ef35ef82790719facd.
Revert "Fix Kbuild"

This reverts commit f4634860fc2fbd357829ac5bcdf4c662784b92b7.
Revert "intelli-thermal v2: initial adaptation"

This reverts commit 3e5232b31753e572e3693602b5f19c1b83fce66f.
Revert "intelli_thermal: compatibility fix up with latest MSM Thermal drivers"

This reverts commit f9d13340a002d81fbde3dd18fe10dfc48fd7d767.
Revert "msm: thermal: Update thermal subsystem"

This reverts commit ad656b31e30759bb58e924436e95dfdf14894680.