Replacing HUGE_VALF with llvm::huge_valf in order to work around a warning triggered in MSVC 12.

Patch reviewed by Reid Kleckner and Jim Grosbach.

llvm-svn: 194533
diff --git a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
index 7a3b305..e1c3217 100644
--- a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -170,7 +170,8 @@
 #endif
 
 LiveInterval* LiveIntervals::createInterval(unsigned reg) {
-  float Weight = TargetRegisterInfo::isPhysicalRegister(reg) ? HUGE_VALF : 0.0F;
+  float Weight = TargetRegisterInfo::isPhysicalRegister(reg) ?
+                  llvm::huge_valf : 0.0F;
   return new LiveInterval(reg, Weight);
 }