sched: Add snapshot of preemption and IRQs disable callers

This snapshot is taken from msm-4.14 as of commit 871eac76e6be567
("Merge "msm: pcie: provide option to override maximum GEN speed"").

Change-Id: I8dc6933a1e3a0835f19c7802930f974d442082a8
Signed-off-by: Satya Durga Srinivasu Prabhala <satyap@codeaurora.org>