[CodeGen][NFC] Update Doxygen references to renamed parameters (#170253)

The parameters were renamed in cfe0393
and 6e70c37.

Author: pfusik

llvm/include/llvm/CodeGen/TargetInstrInfo.h

@@ -1277,7 +1277,7 @@ class LLVM_ABI TargetInstrInfo : public MCInstrInfo {
 
   /// Return true when there is potentially a faster code sequence
   /// for an instruction chain ending in \p Root. All potential patterns are
-  /// returned in the \p Pattern vector. Pattern should be sorted in priority
+  /// returned in the \p Patterns vector. Patterns should be sorted in priority
   /// order since the pattern evaluator stops checking as soon as it finds a
   /// faster sequence.
   /// \param Root - Instruction that could be combined with one of its operands
@@ -1379,7 +1379,7 @@ class LLVM_ABI TargetInstrInfo : public MCInstrInfo {
   /// has to decide whether the actual replacement is beneficial or not.
   /// \param Root - Instruction that could be combined with one of its operands
   /// \param Pattern - Combination pattern for Root
-  /// \param InsInstrs - Vector of new instructions that implement P
+  /// \param InsInstrs - Vector of new instructions that implement Pattern
   /// \param DelInstrs - Old instructions, including Root, that could be
   /// replaced by InsInstr
   /// \param InstIdxForVirtReg - map of virtual register to instruction in