make mapboxgl build on non-Linux platforms

Origin: upstream, https://github.com/mapbox/mapbox-gl-native/commit/5f031dfa56f28d60
Last-Update: 2020-01-08

Gbp-Pq: Name mapboxgl_thread_portability.diff

fix build on Debian GNU/Hurd

Forwarded: no
Last-Update: 2019-12-31

Gbp-Pq: Name hurd_geoclue.diff

remove some include paths to pick up system headers

Forwarded: not-needed
Last-Update: 2020-04-27

Gbp-Pq: Name use_system_dependencies.diff

qtlocation-opensource-src (5.15.8+dfsg-3) unstable; urgency=medium

  * Let the system build the serial plugin by adding libqt5serialport5-dev as
    a build dependency (Closes: #1032394). Thanks Jon Beniston for the bug
    report!

[dgit import unpatched qtlocation-opensource-src 5.15.8+dfsg-3]

Import qtlocation-opensource-src_5.15.8+dfsg-3.debian.tar.xz

[dgit import tarball qtlocation-opensource-src 5.15.8+dfsg-3 qtlocation-opensource-src_5.15.8+dfsg-3.debian.tar.xz]

Import qtlocation-opensource-src_5.15.8+dfsg.orig.tar.xz

[dgit import orig qtlocation-opensource-src_5.15.8+dfsg.orig.tar.xz]