[AbstractAttributor] Refine logic to indicate pessimistic fixed point when folding __kmpc_is_spmd_exec_mode

Since we are using assumed information now, the logic should be refined to avoid
unncessary assertion.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D106630

lib/Transforms/IPO/OpenMPOpt.cpp

@@ -3698,10 +3698,8 @@ private:
       }
     }
 
-    if (KnownSPMDCount && KnownNonSPMDCount)
-      return indicatePessimisticFixpoint();
-
-    if (AssumedSPMDCount && AssumedNonSPMDCount)
+    if ((AssumedSPMDCount + KnownSPMDCount) &&
+        (AssumedNonSPMDCount + KnownNonSPMDCount))
       return indicatePessimisticFixpoint();
 
     auto &Ctx = getAnchorValue().getContext();