tests: build system spring cleanup

 * Remove AC_CONFIG_FILES generated files from check_SCRIPTS and
   EXTRA_DIST since they are already included.
 * Remove useless conditionnals on AC_CONFIG_FILES generated files
   since they are always included.
 * Reduce the number of mostly unused Makefiles
 * Remove execute permission on data files

Change-Id: I4e82bac01bf2033409c67508a4d60127a0e77f14
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/1350
CI-Build: Francis Deslauriers <francis.deslauriers@efficios.com>
Tested-by: jenkins
Reviewed-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Reviewed-by: Philippe Proulx <eeppeliteloop@gmail.com>