[X86] Fix typo in comment in X86FixupLEAs. NFC

Author: topperc

llvm/lib/Target/X86/X86FixupLEAs.cpp

@@ -330,8 +330,8 @@ static inline bool isInefficientLEAReg(unsigned Reg) {
          Reg == X86::R13D || Reg == X86::R13;
 }
 
-/// Returns true if this LEA uses base an index registers, and the base register
-/// is known to be inefficient for the subtarget.
+/// Returns true if this LEA uses base and index registers, and the base
+/// register is known to be inefficient for the subtarget.
 // TODO: use a variant scheduling class to model the latency profile
 // of LEA instructions, and implement this logic as a scheduling predicate.
 static inline bool hasInefficientLEABaseReg(const MachineOperand &Base,