Add kIsSingleSource to PairwiseDistanceEpilogueElementwise (#485)

With raft having recently migrated to cutlass 3.5.1, this field is now required.

Also remove `raft_cutlass` from symbol exclusions.

Authors:
  - Kyle Edwards (https://github.com/KyleFromNVIDIA)

Approvers:
  - Bradley Dice (https://github.com/bdice)
  - Vyas Ramasubramani (https://github.com/vyasr)
  - Micka (https://github.com/lowener)

URL: #485

Author: KyleFromNVIDIA

.github/workflows/pr.yaml

@@ -88,7 +88,7 @@ jobs:
     with:
       build_type: pull-request
       enable_check_symbols: true
-      symbol_exclusions: (void (thrust::|cub::)|raft_cutlass)
+      symbol_exclusions: (void (thrust::|cub::))
   conda-python-build:
     needs: conda-cpp-build
     secrets: inherit

.github/workflows/test.yaml

@@ -23,7 +23,7 @@ jobs:
       date: ${{ inputs.date }}
       sha: ${{ inputs.sha }}
       enable_check_symbols: true
-      symbol_exclusions: (void (thrust::|cub::)|raft_cutlass)
+      symbol_exclusions: (void (thrust::|cub::))
   conda-cpp-tests:
     secrets: inherit
     uses: rapidsai/shared-workflows/.github/workflows/conda-cpp-tests.yaml@branch-24.12

cpp/src/distance/detail/pairwise_distance_epilogue_elementwise.h

@@ -61,6 +61,7 @@ class PairwiseDistanceEpilogueElementwise {
   using ElementT                      = ElementT_;
   static int const kElementsPerAccess = ElementsPerAccess;
   static int const kCount             = kElementsPerAccess;
+  static bool const kIsSingleSource   = true;
 
   using DistanceOp = DistanceOp_;
   using FinalOp    = FinalOp_;