musl: Update to tip of master

Detailed changes [1]

[1] https://git.musl-libc.org/cgit/musl/log/?qt=range&q=040c1d16b468c50c04fc94edff521f1637708328..1b4e84c56df0f8ca30f6bc05962a860f869e71df



Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>