i965: Disable hex offset printing in disassembly.

Printing the hex offsets makes it basically impossible to diff assembly:
if you add even a single instruction, the entire shader shows up as a
difference.  So, every time I want to compare assembly, I have to strip
this out.

The hex offsets might be useful when debugging compaction, or when
inspecting the program cache buffer.  Since it's occasionally useful,
but uncommon, this patch disables it by default, but makes it easy to
re-enable it temporarily when the need arises.

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

src/mesa/drivers/dri/i965/brw_eu.c

@@ -241,7 +241,8 @@ brw_disassemble(struct brw_context *brw,
       brw_inst *insn = assembly + offset;
       brw_inst uncompacted;
       bool compacted = brw_inst_cmpt_control(brw, insn);
-      fprintf(out, "0x%08x: ", offset);
+      if (0)
+         fprintf(out, "0x%08x: ", offset);
 
       if (compacted) {
          brw_compact_inst *compacted = (void *)insn;