Remove __RENAME_STAT64.

Now API level 21 is our lowest supported API level, __RENAME_STAT64 is
useless.

Test: treehugger
Change-Id: I708b2142b30dfcf6c74e1a14475da690a8c25f59
diff --git a/libc/include/sys/stat.h b/libc/include/sys/stat.h
index 54621b7..f773ff6 100644
--- a/libc/include/sys/stat.h
+++ b/libc/include/sys/stat.h
@@ -141,13 +141,13 @@
 int mkdir(const char* _Nonnull __path, mode_t __mode);
 
 int fstat(int __fd, struct stat* _Nonnull __buf);
-int fstat64(int __fd, struct stat64* _Nonnull __buf) __RENAME_STAT64(fstat, 3, 21);
+int fstat64(int __fd, struct stat64* _Nonnull __buf) __INTRODUCED_IN(21);
 int fstatat(int __dir_fd, const char* _Nonnull __path, struct stat* _Nonnull __buf, int __flags);
-int fstatat64(int __dir_fd, const char* _Nonnull __path, struct stat64* _Nonnull __buf, int __flags) __RENAME_STAT64(fstatat, 3, 21);
+int fstatat64(int __dir_fd, const char* _Nonnull __path, struct stat64* _Nonnull __buf, int __flags) __INTRODUCED_IN(21);
 int lstat(const char* _Nonnull __path, struct stat* _Nonnull __buf);
-int lstat64(const char* _Nonnull __path, struct stat64* _Nonnull __buf) __RENAME_STAT64(lstat, 3, 21);
+int lstat64(const char* _Nonnull __path, struct stat64* _Nonnull __buf) __INTRODUCED_IN(21);
 int stat(const char* _Nonnull __path, struct stat* _Nonnull __buf);
-int stat64(const char* _Nonnull __path, struct stat64* _Nonnull __buf) __RENAME_STAT64(stat, 3, 21);
+int stat64(const char* _Nonnull __path, struct stat64* _Nonnull __buf) __INTRODUCED_IN(21);
 
 int mknod(const char* _Nonnull __path, mode_t __mode, dev_t __dev);
 mode_t umask(mode_t __mask);