CFE_TBL_INFO_TABLE_LOCKED should be a negative error code

[thnkslprpt]

Checklist

• I reviewed the Contributing Guide.
• I performed a cursory search to see if the bug report is relevant, not redundant, nor in conflict with other tickets.

Describe the bug
There is an effort in #483 to deprecate/reduce the existence of multiple (non-negative) return codes indicating success.

An easy target to start chipping away at this is CFE_TBL_INFO_TABLE_LOCKED, used in CFE_TBL_UpdateInternal() to signal a locked table and therefore skip the update. Many of the others require refactoring to correct (those in CFE_TBL_Register) or are ambiguous as to whether they should be categorized as error or success.

Code snips

cFE/modules/tbl/fsw/src/cfe_tbl_internal.c

Lines 962 to 967 in 7c03369

	if (LockStatus)
	{
	Status = CFE_TBL_INFO_TABLE_LOCKED;
	CFE_ES_WriteToSysLog("%s: Unable to update locked table Handle=%d\n", __func__, TblHandle);
	}

Expected behavior
This is a clear error (as noted by @jphickey in his analysis in #483) - i.e. nothing was updated. Code should be negative indicating failure/error.

Reporter Info
Avi Weiss @thnkslprpt