ANDROID: Use rq_clock_task without CONFIG_SMP

Fix build error caused by guarding rq_clock_task_mult with CONFIG_SMP.

Issue was not seen in original commit as test case was UM Linux, which
does not enable CONFIG_CFS_BANDWIDTH.

>> kernel/sched/fair.c:4791:40: error: implicit declaration of function 'rq_clock_task_mult' [-Werror,-Wimplicit-function-declaration]
                   cfs_rq->throttled_clock_task_time += rq_clock_task_mult(rq) -

Change-Id: Id3392c37ba1b2bfe78c89bc4b1ca01b920164a35
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 567d65e5 ("ANDROID: Guard rq_clock_task_mult with CONFIG_SMP")
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>