Use MMI->getPersonality() instead of MMI->getPersonalities()[MMI->getPersonalityIndex()]

Also nuke the comment about supporting multiple personalities in a
single function, aka PR1414. That's just crazy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226052 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/MachineModuleInfo.cpp

@@ -554,8 +554,6 @@ try_next:;
 
 /// getPersonality - Return the personality function for the current function.
 const Function *MachineModuleInfo::getPersonality() const {
-  // FIXME: Until PR1414 will be fixed, we're using 1 personality function per
-  // function
   return !LandingPads.empty() ? LandingPads[0].Personality : nullptr;
 }