libmbim: fix build with musl libc

Patch applied upstream:
  https://cgit.freedesktop.org/libmbim/libmbim/commit/?id=417b0b80023dc30d61c111ec0a54da2884d3a541

Fixes:
http://autobuild.buildroot.net/results/dc1/dc11a3dfd18bb7f5078de00412de82de3cce3c48

Signed-off-by: Aleksander Morgado <aleksander@aleksander.es>
[Arnout: rework commit message]
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
1 file changed