formatting: update .clang-format
Updates the formatting rules derived from linux kernel
098b6e44cbaa2d526d06af90c862d13fb414a0ec
At the same time tell clang-format to keep the bespoke formatting
used for the fsm and usb descs.
Change-Id: I1fd4d38897946693b5495fa4d0b61925eb9d07f7
