MachineFunctionProperties/MIRParser: Rename AllVRegsAllocated->NoVRegs, compute it

Rename AllVRegsAllocated to NoVRegs. This avoids the connotation of
running after register and simply describes that no vregs are used in
a machine function. With that we can simply compute the property and do
not need to dump/parse it in .mir files.

Differential Revision: http://reviews.llvm.org/D23850

llvm-svn: 279698
diff --git a/llvm/lib/CodeGen/RegAllocFast.cpp b/llvm/lib/CodeGen/RegAllocFast.cpp
index febb29c..ab74309 100644
--- a/llvm/lib/CodeGen/RegAllocFast.cpp
+++ b/llvm/lib/CodeGen/RegAllocFast.cpp
@@ -165,7 +165,7 @@
 
     MachineFunctionProperties getSetProperties() const override {
       return MachineFunctionProperties().set(
-          MachineFunctionProperties::Property::AllVRegsAllocated);
+          MachineFunctionProperties::Property::NoVRegs);
     }
 
   private: