API header documentation doesn't match c file documentation

[skliper]

Is your feature request related to a problem? Please describe.
Currently the API's are documented in both the .h and .c, and they aren't always consistent. See:

cFE/fsw/cfe-core/src/inc/cfe_sb.h

Lines 947 to 968 in 5802d22

	/*****************************************************************************/
	/**
	** \brief Gets the total length of a software bus message.
	**
	** \par Description
	** This routine returns the total size of the software bus message.
	**
	** \par Assumptions, External Events, and Notes:
	** - For the CCSDS implementation of this API, the size is derived from
	** the message header.
	**
	** \param[in] MsgPtr A pointer to the buffer that contains the software bus message.
	** This must point to the first byte of the message header.
	**
	** \returns
	** \retstmt The total size (in bytes) of the software bus message, including headers. \endstmt
	** \endreturns
	**
	** \sa #CFE_SB_GetUserData, #CFE_SB_GetMsgId, #CFE_SB_GetUserDataLength, #CFE_SB_SetTotalMsgLength,
	** #CFE_SB_GetMsgTime, #CFE_SB_GetCmdCode, #CFE_SB_GetChecksum, #CFE_SB_MsgHdrSize
	**/
	uint16 CFE_SB_GetTotalMsgLength(const CFE_SB_Msg_t *MsgPtr);

vs

cFE/fsw/cfe-core/src/sb/cfe_sb_util.c

Lines 228 to 241 in 5802d22

	/******************************************************************************
	** Function: CFE_SB_GetTotalMsgLength()
	**
	** Purpose:
	** Get the total length of the message which includes the secondary header
	** and the user data field.
	** Does not include the Primary header.
	**
	** Arguments:
	** MsgPtr - Pointer to a CFE_SB_Msg_t
	**
	** Return:
	** Total Length of the message
	*/

Describe the solution you'd like
Document in header only (remove duplicated info in .c), and reference from c files

Describe alternatives you've considered
None

Additional context
Requested by JP/PACE

Requester Info
Jacob Hageman - NASA/GSFC

[skliper]

@jpswinski - FYI