When compiling the components under the arch directory, the compiler
include paths for arch and kernel private headers need to be specified.
This was previously done by adding 'zephyr_library_include_directories'
to CMakeLists.txt file for every component under the arch directory,
and this resulted in a significant amount of duplicate code.
This commit uses the CMake 'include_directories' command in the root
CMakeLists.txt to simplify specification of the private header include
paths for all the arch components.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
7bcfdadf81