[ASan] Replace the call to "vname" with "WRAP(vname)" in FORMAT_INTERCEPTOR_IMPL
It's incorrect to call the function by its name in the interceptor, because that means WRAP(vname) on Linux and REAL(vname) on OSX.

This patch fixes asan/lit_tests/TestCases/printf-3.c on Mac.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@200749 91177308-0d34-0410-b5e6-96231b3b80d8