[NFC] fix trivial typos in comments and documents

"to to" -> "to"

llvm-svn: 323628
diff --git a/llvm/lib/Target/AMDGPU/GCNIterativeScheduler.cpp b/llvm/lib/Target/AMDGPU/GCNIterativeScheduler.cpp
index a0e4f7f..9c6a307 100644
--- a/llvm/lib/Target/AMDGPU/GCNIterativeScheduler.cpp
+++ b/llvm/lib/Target/AMDGPU/GCNIterativeScheduler.cpp
@@ -452,7 +452,7 @@
   // TODO: assert Regions are sorted descending by pressure
   const auto &ST = MF.getSubtarget<SISubtarget>();
   const auto Occ = Regions.front()->MaxPressure.getOccupancy(ST);
-  DEBUG(dbgs() << "Trying to to improve occupancy, target = " << TargetOcc
+  DEBUG(dbgs() << "Trying to improve occupancy, target = " << TargetOcc
                << ", current = " << Occ << '\n');
 
   auto NewOcc = TargetOcc;