iOS: Fix build issue
iOS: Fix build issue

Fix build issue on iOS by adding additional files in lib/gst/player to
the iOS project.

shakin/gst-player,guiseco/gst-player,sdroege/gst-player,amorenoc/gst-player,amorenoc/gst-player,sdroege/gst-player,jabiers/gst-player,amorenoc/gst-player,shakin/gst-player,shakin/gst-player,guiseco/gst-player,codomania/gst-player,JimmyOhn/gst-player,JimmyOhn/gst-player,sdroege/gst-player,guiseco/gst-player,codomania/gst-player,justinjoy/gst-player,justinjoy/gst-player,codomania/gst-player,codomania/gst-player,jabiers/gst-player,sdroege/gst-player,codomania/gst-player,amorenoc/gst-player,justinjoy/gst-player,JimmyOhn/gst-player,amorenoc/gst-player,JimmyOhn/gst-player,JimmyOhn/gst-player,jabiers/gst-player,sdroege/gst-player