configure: surface deprecated targets in the help output

Show the targets but keep them separate from the main list.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20201029201449.6926-1-alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

configure

@@ -1655,9 +1655,11 @@ Standard options:
   --prefix=PREFIX          install in PREFIX [$prefix]
   --interp-prefix=PREFIX   where to find shared libraries, etc.
                            use %M for cpu name [$interp_prefix]
-  --target-list=LIST       set target list (default: build everything)
+  --target-list=LIST       set target list (default: build all non-deprecated)
 $(echo Available targets: $default_target_list | \
   fold -s -w 53 | sed -e 's/^/                           /')
+$(echo Deprecated targets: $deprecated_targets_list | \
+  fold -s -w 53 | sed -e 's/^/                           /')
   --target-list-exclude=LIST exclude a set of targets from the default target-list
 
 Advanced options (experts only):