[gnome-builder] doc: remove build targets from docs

[Christian Hergert <chergert src gnome org>]

commit 837b5c28704e3c24ef6975b3b7c41619340077c7
Author: Christian Hergert <chergert redhat com>
Date:   Sun Nov 19 22:20:53 2017 -0800

    doc: remove build targets from docs

 doc/help/plugins/building/buildsystem.rst |   10 ----------
 1 files changed, 0 insertions(+), 10 deletions(-)
---
diff --git a/doc/help/plugins/building/buildsystem.rst b/doc/help/plugins/building/buildsystem.rst
index e3678cc..4d9fd05 100644
--- a/doc/help/plugins/building/buildsystem.rst
+++ b/doc/help/plugins/building/buildsystem.rst
@@ -37,16 +37,6 @@ Builder has support for many build systems such as autotools, meson, cmake, etc.
            if result.propagate_boolean():
                return result.build_flags
 
-       def do_get_build_targets_async(self, cancellable, callback, data=None):
-           task = Gio.Task.new(self, cancellable, callback)
-           task.build_targets = []
-           # get the build targets
-           task.return_boolean(True)
-
-       def do_get_build_targets_finish(self, result):
-           if result.propagate_boolean():
-               return result.build_targets
-
 
 How does Builder know which build system to use for a project? Each has an associated "project file" 
(configure.ac for autotools) that has to exist in the source directory for the build system to be used. If a 
project has multiple project files, the priorities of each are used to decide which to use. You can see where 
the priority is defined in the code above. The project file is defined in the ``.plugin`` file with these 
lines (in the case of the make plugin):