Initialize new subtarget feature variable for generating reciprocal estimate instructions.

This was missed in r221706.

llvm-svn: 221731

llvm/lib/Target/X86/X86Subtarget.cpp

@@ -274,6 +274,7 @@ void X86Subtarget::initializeEnvironment() {
   SlowLEA = false;
   SlowIncDec = false;
   UseSqrtEst = false;
+  UseReciprocalEst = false;
   stackAlignment = 4;
   // FIXME: this is a known good value for Yonah. How about others?
   MaxInlineSizeThreshold = 128;