Call applyOomAdjLSP starting from the least recently used process.

With this change, in cases where both client and service's oom
scores are updated, their order of killing by LMDK will reflect the
process LRU order, which means least recently used processes will be
killed before most recenlly used processes when they both have the same
oom score.

There are some cases where client's oom score is not updated, and its
position in LMKD queue does not get updated, resulting service to appear
closer to the most recently used end and getting killed after the
client (again if they have the same oom score, i.e. bound with
BIND_IMPORTANT flag). These cases will not benefit from this change,
but also would not get worse, since this is the current behavior before
this CL.

But in many cases, for example when app goes to background and get prev
oom score, or when the app gets cached, both the client and service
processes get updated. And this is when the most killing happen,
increasing the benefits of this change, without any side effects.

Also, this change will only be helpful if LMKD keeps having FIFO killing
order.

Bug: 378580264
Test: atest MockingOomAdjusterTests#testUpdateOomAdj_ApplyOomAdjInCorrectOrder
Flag: com.android.server.am.fix_apply_oomadj_order
Change-Id: I53d06354abaf0d5ce34f8d7a006579226c9254ae