Fix the test issue RM#3505137 (#9301)

Use gre type 0x8949 when it is Nvidia platform.

tests/dualtor/test_ipinip.py

@@ -231,7 +231,9 @@ def setup_mirror_session(rand_selected_dut, setup_uplink):
     The mirror session is to trigger the issue. No packet is mirrored actually.
     """
     session_name = "dummy_session"
-    cmd = "config mirror_session add {} 25.192.243.243 20.2.214.125 8 100 1234 0".format(session_name)
+    # Nvidia platforms support only the gre_type 0x8949, which is 35145 in decimal.
+    gre_type = 35145 if "mellanox" == rand_selected_dut.facts['asic_type'] else 1234
+    cmd = "config mirror_session add {} 25.192.243.243 20.2.214.125 8 100 {} 0".format(session_name, gre_type)
     rand_selected_dut.shell(cmd=cmd)
     uplink_port_id = setup_uplink
     yield uplink_port_id