i965: Nuke brw_wm_glsl.c.

i965: Nuke brw_wm_glsl.c.

It was only used for gen6 fragment programs (not GLSL shaders) at this
point, and it was clearly unsuited to the task -- missing opcodes,
corrupted texturing, and assertion failures hit various applications
of all sorts.  It was easier to patch up the non-glsl for remaining
gen6 changes than to make brw_wm_glsl.c complete.

Bug #30530