i965/fs: Log a performance warning if skipping 16-wide due to pulls.

i965/fs: Log a performance warning if skipping 16-wide due to pulls.

Usually, the driver creates both 8-wide and 16-wide variants of every
fragment shader.  When 16-wide compilation fails, it logs a performance
warning explaining why only an 8-wide program exists.

However, when there are pull parameters, the driver won't even bother
trying the 16-wide compile (since it would fail).  In this case, it
failed to emit a performance warning, leaving no explanation for the
missing 16-wide program.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>