Fix warnings with -Wall -Wextra enabled

[tony-josi-aws]

Issue #, if available:

When library is compiled with -Wextra on ARM GCC compiler (arm-none-eabi-gcc) the following warnings are emitted:

(base) [δ:0s T:15:39:04]ubuntu@ip-172-31-69-236:~/Projects/Fleet-Provisioning-for-AWS-IoT-embedded-sdk$ arm-none-eabi-gcc -std=gnu99 -ggdb -DNDEBUG -mcpu=cortex-m4 -mthumb -mfloat-abi=hard -mfpu=fpv4-sp-d16 source/fleet_provisioning.c -c -I source/include -DFLEET_PROVISIONING_DO_NOT_USE_CUSTOM_CONFIG -Wall -Wextra
source/fleet_provisioning.c: In function 'GetRegisterThingTopicCheckParams':
source/fleet_provisioning.c:289:18: warning: comparison is always false due to limited range of data type [-Wtype-limits]
  289 |         ( format < FleetProvisioningJson ) ||
      |                  ^
source/fleet_provisioning.c:291:17: warning: comparison is always false due to limited range of data type [-Wtype-limits]
  291 |         ( topic < FleetProvisioningPublish ) ||
      |                 ^

Description of changes:

This PR fixes that by removing the ( format < FleetProvisioningJson ) and ( topic < FleetProvisioningPublish ) checks as they are always false. format and topic are of the type FleetProvisioningFormat_t and FleetProvisioningApiTopics_t, thus wont be less than the minimum values FleetProvisioningJson and FleetProvisioningPublish respectively.

• I have tested my changes. No regression in existing tests.
• [ ] I have modified and/or added unit-tests to cover the code changes in this Pull Request.

By submitting this pull request, I confirm that my contribution is made under the terms of the MIT license.