patman: Add the concept of multiple projects

There are cases that we want to support different settings (or maybe
even different aliases) for different projects.  Add support for this
by:
* Adding detection for two big projects: U-Boot and Linux.
* Adding default settings for Linux (U-Boot is already good with the
  standard patman defaults).
* Extend the new "settings" feature in .patman to specify per-project
  settings.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/patman/README b/tools/patman/README
index 2743da9..1832ebd 100644
--- a/tools/patman/README
+++ b/tools/patman/README
@@ -114,6 +114,19 @@
 <<<
 
 
+If you want to adjust settings (or aliases) that affect just a single
+project you can add a section that looks like [project_settings] or
+[project_alias].  If you want to use tags for your linux work, you could
+do:
+
+>>>
+
+[linux_settings]
+process_tags: True
+
+<<<
+
+
 How to run it
 =============