platform: do not pass a directory on the command line.
The home directory will be properly set by Device.home_dir.
It was sometimes crashing when opened with no args.
Fixes: #7049
* remove unused setting 'internal_storage_mount_point
use filemanagerutil.getDefaultDir() instead
https://github.com/koreader/koreader/blob/master/frontend/apps/filemanager/filemanagerutil.lua#L15
* more info about device frontlight/naturalLight capabilities
* make stock reader fonts available in KOReader
* remove restore-wifi-async leftovers
* wireless: fix wpa_supplicant configuration:
make it compatible w/ debian wheezy binaries
don't try to run enable-wifi.sh more than once