* libio/stdio_ext.h: Moved to ...
* stdio-common/stdio_ext.h: ... here.
* libio/Makefile (headers): Move stdio_ext.h from here ...
* stdio-common/Makefile (headers): ... to here.
* include/stdio_ext.h: New file.
* stdio/Makefile (routines): Add the stdio_ext.h functions here.
* stdio/Versions (GLIBC_2.2.4): Export the stdio_ext.h functions.
* stdio/__flbf.c: New file.
* stdio/__fbufsize.c: New file.
* stdio/__fpending.c: New file.
* stdio/__fpurge.c: New file.
* stdio/__freadable.c: New file.
* stdio/__freading.c: New file.
* stdio/__fsetlocking.c: New file.
* stdio/__fwritable.c: New file.
* stdio/__fwriting.c: New file.
