pan/midgard: Allow fusing inverted sources for inverted ops

It doesn't make a difference to the actual algorithm, so let's get rid
of them.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3978>

src/panfrost/midgard/midgard_opt_invert.c

@@ -242,7 +242,6 @@ midgard_opt_fuse_src_invert(compiler_context *ctx, midgard_block *block)
                 /* Search for inverted bitwise */
                 if (ins->type != TAG_ALU_4) continue;
                 if (!mir_is_bitwise(ins)) continue;
-                if (ins->invert) continue;
 
                 if (!is_ssa_or_constant(ins->src[0])) continue;
                 if (!is_ssa_or_constant(ins->src[1])) continue;