Revert "Export the INCLUDES DESTINATION without appending to the target."

This reverts commit 2e18259d1622806808d4d6e0372596ed136941a4.
Revert "Add a convenient way to add the includes install dir to the INTERFACE."

This reverts commit 537ab88be837f33903663afcbe9da33f13c727a1.
Merge topic 'install-interface-includes' into next

451acd9 Revert "Add a convenient way to add the includes install dir to the INTERFACE."
384768e Revert "Export the INCLUDES DESTINATION without appending to the target."