List ssl_debug_helpers_generated.h in generated files

Running `generate_ssl_debug_helpers.py` generates both
`ssl_debug_helpers_generated.c` and `ssl_debug_helpers_generated.h`.

List the `.h` file as well as the `.c` file in `check-generated-files.sh` so
that `check-generated-files.sh -u` will complain if it isn't up to date.

List it in `Makefile` and `CMakeLists.txt` so that parallel builds know when
to wait until the `.h` file is present. In `Makefile`, declare the `.c` file
as depending on the `.h` file for order. This way, a dependency for either
will wait until the `.h` file is present, and since the `.h` file is
generated after the `.c` file, this guarantees that the `.c` file is
present.

This fixes random failures of `make -j` from a fresh checkout.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/scripts/check-generated-files.sh b/tests/scripts/check-generated-files.sh
index 994fd24..b35da3d 100755
--- a/tests/scripts/check-generated-files.sh
+++ b/tests/scripts/check-generated-files.sh
@@ -118,7 +118,7 @@
 check scripts/generate_errors.pl library/error.c
 check scripts/generate_query_config.pl programs/test/query_config.c
 check scripts/generate_features.pl library/version_features.c
-check scripts/generate_ssl_debug_helpers.py library/ssl_debug_helpers_generated.c
+check scripts/generate_ssl_debug_helpers.py library/ssl_debug_helpers_generated.h library/ssl_debug_helpers_generated.c
 # generate_visualc_files enumerates source files (library/*.c). It doesn't
 # care about their content, but the files must exist. So it must run after
 # the step that creates or updates these files.