[Hexagon] Remove unnecessary llvm::, NFC

llvm-svn: 279244

llvm/lib/Target/Hexagon/BitTracker.cpp

@@ -1050,7 +1050,7 @@ bool BT::reached(const MachineBasicBlock *B) const {
 
 // Visit an individual instruction. This could be a newly added instruction,
 // or one that has been modified by an optimization.
-void BT::visit(const llvm::MachineInstr &MI) {
+void BT::visit(const MachineInstr &MI) {
   assert(!MI.isBranch() && "Only non-branches are allowed");
   InstrExec.insert(&MI);
   visitNonBranch(MI);