Add a legacy inline for mmap64.

While this was never an inline, this function alone has caused most of
the bug reports related to _FILE_OFFSET_BITS=64. Providing an inline
for it should allow a lot more code to build with _FILE_OFFSET_BITS=64
when targeting pre-L.

Test: make checkbuild
Test: built trivial cc_binary for LP32 against API 14 with
      _FILE_OFFSET_BITS=64 set
Bug: lots
Change-Id: I8479d34af4da358c11423bee43d45b59e9d4143e
diff --git a/libc/malloc_debug/malloc_debug.cpp b/libc/malloc_debug/malloc_debug.cpp
index d890a1c..a2ada2f 100644
--- a/libc/malloc_debug/malloc_debug.cpp
+++ b/libc/malloc_debug/malloc_debug.cpp
@@ -767,7 +767,7 @@
   }
 
   size_t pagesize = getpagesize();
-  size_t size = BIONIC_ALIGN(bytes, pagesize);
+  size_t size = __BIONIC_ALIGN(bytes, pagesize);
   if (size < bytes) {
     // Overflow
     errno = ENOMEM;