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/include/sys/cdefs.h b/libc/include/sys/cdefs.h
index 063b51d..3656733 100644
--- a/libc/include/sys/cdefs.h
+++ b/libc/include/sys/cdefs.h
@@ -79,6 +79,8 @@
 #define __BIONIC_CAST(_k,_t,_v) ((_t) (_v))
 #endif
 
+#define __BIONIC_ALIGN(__value, __alignment) (((__value) + (__alignment)-1) & ~((__alignment)-1))
+
 /*
  * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
  * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.