New makefile component_wrapper.mk allows some variables to be set
before component.mk is evaluated. This properly fixes problems with
sdkconfig being hard to access in all phases of the build.
Including component_common.mk is no longer necessary and will print a
deprecation warning for components which use it.
Fixes problems with Eclipse trying to build in directories it shouldn't.
This is a breaking change for existing repositories, they need to rename
any component Makefiles to component.mk and rename their references to
$(IDF_PATH)/make/component.mk to $(IDF_PATH)/make/component_common.mk
Angus Gratton