texture: Remove GStaticMutex
texture: Remove GStaticMutex

It's now possible to statically initialize a GMutex.

kerrickstaley/clutter-vala,GNOME/clutter,GNOME/clutter,ebassi/clutter,Distrotech/clutter,jigpu/clutter,Distrotech/clutter,Distrotech/clutter,collects/clutter,GNOME/clutter,kerrickstaley/clutter-vala,heysion/clutter-clone,Distrotech/clutter,djdeath/clutter-android,ebassi/clutter,ebassi/clutter,djdeath/clutter,Distrotech/clutter,collects/clutter,ebassi/clutter,jigpu/clutter,djdeath/clutter-multithreaded,djdeath/clutter-multithreaded,heysion/clutter-clone,djdeath/clutter-multithreaded,jigpu/clutter,kerrickstaley/clutter-vala,djdeath/clutter,heysion/clutter-clone,collects/clutter,heysion/clutter-clone,jigpu/clutter,djdeath/clutter-android,jigpu/clutter,GNOME/clutter,djdeath/clutter,djdeath/clutter,ebassi/clutter,collects/clutter,GNOME/clutter,Distrotech/clutter,jigpu/clutter,djdeath/clutter-android,djdeath/clutter-android,djdeath/clutter,kerrickstaley/clutter-vala,collects/clutter,djdeath/clutter,djdeath/clutter-android,djdeath/clutter-multithreaded,heysion/clutter-clone