Bug 41959: (QA follow-up) Add missing POD

Signed-off-by: Martin Renvoize <martin.renvoize@openfifth.co.uk>
(cherry picked from commit 0d84b49ea7)
Signed-off-by: Jacob O'Mara <Jacob.omara@openfifth.co.uk>

C4/HoldsQueue.pm

@@ -439,6 +439,15 @@ sub _checkHoldPolicy {
 
 }
 
+=head2 _allocateWithTransportCostMatrix
+
+    _allocateWithTransportCostMatrix( $hold_requests, $available_items, $branches_to_use, $libraries,
+        $transport_cost_matrix, $allocated_items, $items_by_itemnumber )
+
+    given a list of  holds and items attempt to fill the holds in the 'least cost' order
+
+=cut
+
 sub _allocateWithTransportCostMatrix {
     my (
         $hold_requests, $available_items, $branches_to_use, $libraries, $transport_cost_matrix, $allocated_items,
@@ -1131,6 +1140,12 @@ sub AddToHoldTargetMap {
 
 # Helper functions, not part of any interface
 
+=head2 _trim
+
+Remove leading and trailing spaces
+
+=cut
+
 sub _trim {
     return $_[0] unless $_[0];
     $_[0] =~ s/^\s+//;