cogl: call _cogl_texture_init for x11 tfp
cogl: call _cogl_texture_init for x11 tfp

When we added the texture->framebuffers member a _cogl_texture_init
funciton was added to initialize the list of framebuffers associated
with a texture to NULL. All the backends were updated except the
x11 tfp backend. This was causing crashes in test-pixmap.

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