[dev] fix trt nms error output in ppyoloe (#6607)

ppdet/modeling/layers.py

@@ -481,8 +481,9 @@ class MultiClassNMS(object):
             # TODO(wangxinxin08): tricky switch to run nms on tensorrt
             kwargs.update({'nms_eta': 1.1})
             bbox, bbox_num, _ = ops.multiclass_nms(bboxes, score, **kwargs)
-            mask = paddle.slice(bbox, [-1], [0], [1]) != -1
-            bbox = paddle.masked_select(bbox, mask).reshape((-1, 6))
+            bbox = bbox.reshape([1, -1, 6])
+            idx = paddle.nonzero(bbox[..., 0] != -1)
+            bbox = paddle.gather_nd(bbox, idx)
             return bbox, bbox_num, None
         else:
             return ops.multiclass_nms(bboxes, score, **kwargs)
@@ -1353,7 +1354,7 @@ class ConvMixer(nn.Layer):
         Seq, ActBn = nn.Sequential, lambda x: Seq(x, nn.GELU(), nn.BatchNorm2D(dim))
         Residual = type('Residual', (Seq, ),
                         {'forward': lambda self, x: self[0](x) + x})
-        return Seq(* [
+        return Seq(*[
             Seq(Residual(
                 ActBn(
                     nn.Conv2D(