fix some wrong args for ch_PP-OCRv2_rec

test_tipc/configs/ch_PP-OCRv2_rec/train_infer_python.txt

@@ -26,7 +26,7 @@ null:null
 ##
 ===========================infer_params===========================
 Global.save_inference_dir:./output/
-Global.pretrained_model:
+Global.checkpoints:
 norm_export:tools/export_model.py -c test_tipc/configs/ch_PP-OCRv2_rec/ch_PP-OCRv2_rec_distillation.yml -o 
 quant_export:
 fpgm_export: 

test_tipc/configs/ch_PP-OCRv2_rec_PACT/train_infer_python.txt

@@ -26,7 +26,7 @@ null:null
 ##
 ===========================infer_params===========================
 Global.save_inference_dir:./output/
-Global.pretrained_model:
+Global.checkpoints:
 norm_export:null
 quant_export:deploy/slim/quantization/export_model.py -c test_tipc/configs/ch_PP-OCRv2_rec/ch_PP-OCRv2_rec_distillation.yml -o 
 fpgm_export: null

test_tipc/configs/ch_ppocr_mobile_v2.0_rec_PACT/train_infer_python.txt

@@ -34,7 +34,7 @@ distill_export:null
 export1:null
 export2:null
 inference_dir:null
-train_model:./inference/ch_ppocr_mobile_v2.0_rec_slim_infer/
+infer_model:./inference/ch_ppocr_mobile_v2.0_rec_slim_infer/
 infer_export:null
 infer_quant:False
 inference:tools/infer/predict_rec.py --rec_char_dict_path=./ppocr/utils/ppocr_keys_v1.txt --rec_image_shape="3,32,100"