Is it possible to get different "exit code" ?

**Is your feature request related to a problem? Please describe.**

Goal is to use `mbedtools compile xxx`` commands in scripts.

It seems that "exit code" is currently 0 when it is successful, 1 in case of issue.

**Describe the solution you'd like**

Do you think it is possible to have more error codes ?

- 1 would be the default error code
- 2 for issue in **mbed_validate_application_profile** function?
- 3 in case of CMakeLists.txt configuration issue?
- etc...

**Describe alternatives you've considered**
A clear and concise description of any alternative solutions or features you've considered.

**Additional context**
Add any other context or screenshots about the feature request here.

Start with the mbedtools compile xxx command and trace how it currently returns 0 or 1, then inspect mbed_validate_application_profile and CMakeLists.txt handling. Done means the supported error-code mapping is defined for the requested failure categories and verified through compile commands used in scripts.

Written by the indexing model from the issue text.