Fix missing stanza in 3P preproc log parser

Docker/parse_logs

@@ -177,6 +177,10 @@ sub parse_3P_preproc {
     my @preproc_s = ();
     my @preproc_kib = ();
     while(<>) {
+        if (/===== P([012]) output/) {
+            $who = $1;
+            next;
+        }
         last if /===== End/;
         if (/WallClockTime: (\d+\.?\d*)/) {
             $preproc_s[$who] = $1;