When calling a non variadic format function(vprintf, vscanf, NSLogv, …), warn...

When calling a non variadic format function(vprintf, vscanf, NSLogv, …), warn if the format string argument is a parameter that is not itself declared as a format string with compatible format.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151080 91177308-0d34-0410-b5e6-96231b3b80d8