Fix a missing MakeCurrent in glamor_egl_create_argb8888_based_texture

There is a missing MakeCurrent before creating the texture
and link it to the EGLImage.

This fixes an X server crash with the piglit test
glx-make-current-multi-process on radeonsi from current Mesa Git.

Signed-off-by: Axel Davy <axel.davy@ens.fr>
Tested-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>