[ASan/Win] Introduce a new macro for malloc-like function attributes; also, clang-format the definitions of these functions

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@215724 91177308-0d34-0410-b5e6-96231b3b80d8
Follow-up to r215724: fix a lint warning

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@215725 91177308-0d34-0410-b5e6-96231b3b80d8