Bluetooth: Map: Trim folder name in pushMessage and setPath

Trim folder name string passed from remote, before processing the
pushMessage and setPath request to do proper handling when a blank
folder name is passed from some Carkits. Without this change there
will be some IOT issues with some carkit(s) which will append a space
instead of empty string for pushing message to current folder.

Change-Id: I8b0bdfc1f837c53f0773057db27b81ae9acb279a