i965/fs: Fix broken rendering in large shaders with UBO loads.

The lowering process creates a new vgrf on gen7 that should be represented
in live interval analysis.  As-is, it was getting a conflicting allocation
with gl_FragDepth in the dolphin emulator, producing broken rendering.

NOTE: This is a candidate for the 9.1 branch.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61317
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
1 file changed