Unit test status code discrepancies in osapi-timer.h

[jphickey]

Is your feature request related to a problem? Please describe.
The unit tests and API documentation should match, where all status codes in the API documentation are tested in a unit test, and likewise all codes being tested for are documented in the API.

Describe the solution you'd like
Resolve the following mismatches:

File src/os/inc/osapi-timer.h, function OS_TimerCreate():

• OK: OS_ERR_NAME_TAKEN
• OK: OS_ERR_NAME_TOO_LONG
• OK: OS_ERR_NO_FREE_IDS
• OK: OS_INVALID_POINTER
• OK: OS_SUCCESS
• ONLY IN DOXY: OS_TIMER_ERR_INVALID_ARGS
• ONLY IN DOXY: OS_TIMER_ERR_UNAVAILABLE

File src/os/inc/osapi-timer.h, function OS_TimerAdd():

File src/os/inc/osapi-timer.h, function OS_TimerSet():

• ONLY IN DOXY: OS_ERROR
• ONLY IN DOXY: OS_ERR_INCORRECT_OBJ_STATE
• OK: OS_ERR_INVALID_ID
• OK: OS_SUCCESS
• ONLY IN DOXY: OS_TIMER_ERR_INTERNAL
• ONLY IN DOXY: OS_TIMER_ERR_INVALID_ARGS

File src/os/inc/osapi-timer.h, function OS_TimerDelete():

• ONLY IN DOXY: OS_ERR_INCORRECT_OBJ_STATE
• OK: OS_ERR_INVALID_ID
• OK: OS_SUCCESS
• ONLY IN DOXY: OS_TIMER_ERR_INTERNAL

File src/os/inc/osapi-timer.h, function OS_TimerGetIdByName():

• ONLY IN DOXY: OS_ERR_INCORRECT_OBJ_STATE
• OK: OS_ERR_NAME_NOT_FOUND
• OK: OS_ERR_NAME_TOO_LONG
• OK: OS_INVALID_POINTER
• OK: OS_SUCCESS

File src/os/inc/osapi-timer.h, function OS_TimerGetInfo():

• ONLY IN DOXY: OS_ERR_INCORRECT_OBJ_STATE
• OK: OS_ERR_INVALID_ID
• OK: OS_INVALID_POINTER
• OK: OS_SUCCESS

Additional context
Originally noted in #331, split into separate work items.

Requester Info
Joseph Hickey, Vantage Systems, Inc.