[CodeGen] Use llvm::has_single_bit (NFC) (#143394)

Author: kazutakahirata

llvm/include/llvm/CodeGen/ScoreboardHazardRecognizer.h

@@ -59,7 +59,7 @@ class ScoreboardHazardRecognizer : public ScheduleHazardRecognizer {
 
     InstrStage::FuncUnits& operator[](size_t idx) const {
       // Depth is expected to be a power-of-2.
-      assert(Depth && !(Depth & (Depth - 1)) &&
+      assert(llvm::has_single_bit(Depth) &&
              "Scoreboard was not initialized properly!");
 
       return Data[(Head + idx) & (Depth-1)];