Bug 1875275

Description of problem:
Running sysjitter workload on a system running with tuned cpu-partitioning
profile results in an excessive number of interrupts.

Debugging performed in bz1833196 resulted in a set of patches to reduce
perturbation from timers, however it also highlighted that we still need
to fix an additional case related to the scheduler use of SD_LOAD_BALANCE
flag (bz1833196#c38).

This is to track resolution of the remaining issue, either backporting
upstream patches that removes SD_LOAD_BALANCE flag or the RHEL only fix
proposed in the bz above (bz1833196#c48).

Steps to Reproduce:
1. install perf and sysjitter (https://github.com/alexeiz/sysjitter)
2. start cpu-partitioning profile with isolated and nonbalance cpus
3. perf stat -C 4 -e irq_vectors:local_timer_entry taskset --cpu-list 4 ./sysjitter/sysjitter --runtime 10 200 (on an isolated/non balance cpu)

Actual results:
Very high number (thousand) of irq_vectors:local_timer_entry events, e.g.

[root@rt-qe-04 ~]# perf stat -C 4 -e irq_vectors:local_timer_entry taskset --cpu-list 4 ./sysjitter/sysjitter --runtime 10 200
core_i: 4
threshold(ns): 200
cpu_mhz: 2398
runtime(ns): 9995739030
runtime(s): 9.996
int_n: 10005
int_n_per_sec: 1000.927
int_min(ns): 2760
int_median(ns): 6025
int_mean(ns): 6056
int_90(ns): 6086
int_99(ns): 6685
int_999(ns): 6775
int_9999(ns): 8123
int_99999(ns): 12657
int_max(ns): 12657
int_total(ns): 60598000
int_total(%): 0.606

 Performance counter stats for 'CPU(s) 4':

            11,007      irq_vectors:local_timer_entry

Expected results:
Very low number (double digit) of irq_vectors:local_timer_entry events

[root@rt-qe-04 ~]# perf stat -C 4 -e irq_vectors:local_timer_entry taskset --cpu-list 4 ./sysjitter/sysjitter --runtime 10 200
core_i: 4
threshold(ns): 200
cpu_mhz: 2398
runtime(ns): 9995639269
runtime(s): 9.996
int_n: 4
int_n_per_sec: 0.400
int_min(ns): 2807
int_median(ns): 6078
int_mean(ns): 5721
int_90(ns): 10602
int_99(ns): 10602
int_999(ns): 10602
int_9999(ns): 10602
int_99999(ns): 10602
int_max(ns): 10602
int_total(ns): 22887
int_total(%): 0.000

 Performance counter stats for 'CPU(s) 4':

                42      irq_vectors:local_timer_entry