ir3: initialize progress false before ir3_nir_lower_imul

Removes a compiler warning about uninitialized variable.

Fixes: c02ffd2700 "ir3: Use the new NIR lowering pass for integer multiplication"
Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Rob Clark <robclark@gmail.com>
Reviewed-by: Eduardo Lima <elima@igalia.com>

src/freedreno/ir3/ir3_context.c

@@ -90,7 +90,7 @@ ir3_context_init(struct ir3_compiler *compiler,
 	 * However, we want a final swing of a few passes to have a chance
 	 * at optimizing the result.
 	 */
-	bool progress;
+	bool progress = false;
 	NIR_PASS(progress, ctx->s, ir3_nir_lower_imul);
 	if (progress) {
 		NIR_PASS_V(ctx->s, nir_opt_algebraic);