Since !2190, source files located outside of the component root
produce object files inside build directory. This change fixes
handling of COMPONENT_OBJEXCLUDE variable for such files. Tests are
added.
For config-only components, component.mk should now contain "COMPONENT_CONFIG_ONLY := 1"
Also refactored some of the generation of linker paths, library list. This required cleaning up the way the bootloader
project works, it's now mostly independent from the parent.
Now the tests do not pass
Before we had incorrect code of the error code checking
in build_examples.sh for that case and did nothing in test_build_system.sh.
Ivan Grokhotkov