[Mellanox] [202012] Fix issue: 4600C is using wrong thermal profile (s…

…onic-net#10258)

- Why I did it
4600C is using wrong thermal profile and it displays 2 CPU core thermal in show platform temperature output, there should be 4 CPU core thermal.

- How I did it
Change 4600C to use thermal profile 10.

- How to verify it
Manual test

platform/mellanox/mlnx-platform-api/sonic_platform/thermal.py

@@ -142,7 +142,7 @@
 platform_dict_thermal = {'x86_64-mlnx_msn2700-r0': 0, 'x86_64-mlnx_lssn2700-r0': 0, 'x86_64-mlnx_msn2740-r0': 3,
                          'x86_64-mlnx_msn2100-r0': 1, 'x86_64-mlnx_msn2410-r0': 2, 'x86_64-mlnx_msn2010-r0': 4,
                          'x86_64-mlnx_msn3420-r0': 9, 'x86_64-mlnx_msn3700-r0': 5, 'x86_64-mlnx_msn3700c-r0': 6,
-                         'x86_64-mlnx_msn3800-r0': 7, 'x86_64-mlnx_msn4600-r0': 12, 'x86_64-mlnx_msn4600c-r0': 9,
+                         'x86_64-mlnx_msn3800-r0': 7, 'x86_64-mlnx_msn4600-r0': 12, 'x86_64-mlnx_msn4600c-r0': 10,
                          'x86_64-mlnx_msn4700-r0': 8, 'x86_64-mlnx_msn4410-r0': 8}
 thermal_profile_list = [
     # 0 2700