mbedTLS: Small cleanup
mbedTLS: Small cleanup

* Remove empty lines
* Add/Remove extra space
* Remove commented code
* Add static qualifer to variables

Signed-off-by: Francois Berder <0eabc3e9da54407da074ac08d4217d54f5b94915@imgtec.com>

DavidAntliff/AwaLWM2M,DavidAntliff/AwaLWM2M,DavidAntliff/AwaLWM2M,DavidAntliff/AwaLWM2M,FlowM2M/AwaLWM2M,FlowM2M/AwaLWM2M,FlowM2M/AwaLWM2M,FlowM2M/AwaLWM2M