ios: Use -Wno-error=implicit-function-declaration
ios: Use -Wno-error=implicit-function-declaration

Many configure checks use implicit function declarations and fail because of
this now on iOS x86-64. The new XCode makes them errors instead of warnings.

nzjrs/cerbero,shoreflyer/cerbero,shoreflyer/cerbero,justinjoy/cerbero,ramaxlo/cerbero,GStreamer/cerbero,flexVDI/cerbero,shoreflyer/cerbero,multipath-rtp/cerbero,justinjoy/cerbero,AlertMe/cerbero,multipath-rtp/cerbero,lubosz/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,centricular/cerbero,centricular/cerbero,flexVDI/cerbero,shoreflyer/cerbero,AlertMe/cerbero,brion/cerbero,nirbheek/cerbero,shoreflyer/cerbero,sdroege/cerbero,atsushieno/cerbero,OptoFidelity/cerbero,fluendo/cerbero,nirbheek/cerbero-old,jackjansen/cerbero,nzjrs/cerbero,EricssonResearch/cerbero,superdump/cerbero,flexVDI/cerbero,ford-prefect/cerbero,superdump/cerbero,EricssonResearch/cerbero,EricssonResearch/cerbero,GStreamer/cerbero,atsushieno/cerbero,nzjrs/cerbero,ikonst/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,nzjrs/cerbero,nzjrs/cerbero,nirbheek/cerbero,nirbheek/cerbero-old,GStreamer/cerbero,sdroege/cerbero,brion/cerbero,multipath-rtp/cerbero,atsushieno/cerbero,EricssonResearch/cerbero,brion/cerbero,GStreamer/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,atsushieno/cerbero,AlertMe/cerbero,multipath-rtp/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,fluendo/cerbero,OptoFidelity/cerbero,fluendo/cerbero,ford-prefect/cerbero,ramaxlo/cerbero,GStreamer/cerbero,ford-prefect/cerbero,jackjansen/cerbero,centricular/cerbero,ikonst/cerbero,sdroege/cerbero,OptoFidelity/cerbero,centricular/cerbero,lubosz/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,fluendo/cerbero,flexVDI/cerbero,AlertMe/cerbero,AlertMe/cerbero,nirbheek/cerbero,centricular/cerbero,fluendo/cerbero,ramaxlo/cerbero,jackjansen/cerbero,ramaxlo/cerbero,lubosz/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,ford-prefect/cerbero,brion/cerbero,ikonst/cerbero,brion/cerbero,superdump/cerbero,nirbheek/cerbero-old,superdump/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,ramaxlo/cerbero,jackjansen/cerbero,atsushieno/cerbero,ikonst/cerbero,OptoFidelity/cerbero,flexVDI/cerbero,sdroege/cerbero,multipath-rtp/cerbero,ikonst/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,nirbheek/cerbero-old,lubosz/cerbero,nirbheek/cerbero,EricssonResearch/cerbero,justinjoy/cerbero,sdroege/cerbero,justinjoy/cerbero