GitLab

While this component is stored in pre-compiled form, we need the header filenames to be converted to postfix-extension form during the export phase so that compilers and other code analysis tools will find them. Because this is a somewhat unusual component, this is achieved with a custom makefile for cross-compilation use. Support is also included for converting the object files to ELF format when exporting, if ${TOOLCHAIN} is GNU.

Enable GitLab CI (native Makefile given partial GNU make compatibility to facilite some of the CI jobs, and as a side-effect will enable correct syntax colouring in GitLab).

NOT_USED macro refactored to avoid cppcheck warnings in clients. It now evaluates its argument only once, so is more function-lilke, but sadly has to remain a compound statement because a few components use it without a trailing semicolon.