Update number of nodes passed to Mira qsub

CIME 5.2 fixed $TOTALPES, which was incorrect in CIME 5.1. This sets
the number of nodes passed to qsub as $TOTALPES/$PES_PER_NODE.

cime_config/acme/machines/config_batch.xml

@@ -44,8 +44,7 @@
        <arg flag="--cwd" name="CASEROOT"/>
        <arg flag="-A" name="PROJECT"/>
        <arg flag="-t" name="JOB_WALLCLOCK_TIME"/>
-       <!-- ceiling of $a/$b is ($a+$b-1)/$b -->
-       <arg flag="-n" name=" ( $TOTALPES + $MAX_TASKS_PER_NODE - 1 ) / $MAX_TASKS_PER_NODE"/>
+       <arg flag="-n" name=" $TOTALPES/$PES_PER_NODE"/>
        <arg flag="-q" name="JOB_QUEUE"/>
        <arg flag="--mode script"/>
      </submit_args>