mesa: add plumbing for GL_ARB_texture_query_levels

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
glsl: add plumbing for GL_ARB_texture_query_levels

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
i965: ignore all texturing opcodes without a coordinate, for cubemap normalize

Previously we special-cased textureSize() but this is the more correct
condition.

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
i965/fs: implement ir_query_levels

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
i965/vs: implement ir_query_levels

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>