Add raw config load support

There are multiple formats for representing device configuration. This adds
support for loading the OBP_RAW format, which is a simple ASCII hex
representation of the config data. Saving this format was already supported.

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Fix erroneous "Skipping version check" output

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Output newline to correct stream when logging

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Adjust debug levels of some logging

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Minor improvement to .xcfg parsing

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Add newline to end of version output

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Improve return codes in error handling

 - Add new enum to allocate error codes to all error paths
 - Convert libusb and errno-based APIs to mxt_rc scheme
 - Refactor functions that overload return code to split out

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Log to stdout when in menu mode

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Attempt to recover from bootloader stuck

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>