musl: get rid of more stdio files with trivial changes

Get rid of several files which are identical to Musl except trivial
changes, like adding an (unnecessary) header #include, or changing
an include from < to ".

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>