[libc++] Pair _aligned_malloc with _aligned_free
Attempting to pair an _aligned_malloc with a regular free causes heap
corruption. Pairing with _aligned_free is required instead.
Makes the following libc++ tests pass on Windows:
std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp
Differential Revision: https://reviews.llvm.org/D28512
llvm-svn: 291743