devtool: add support for git submodules

Adding the support of submodules required a lot of changes on the
internal data structures:
* initial_rev/startcommit used as a starting point for looking at new
  / updated commits was replaced by a dictionary where the keys are the
  submodule name ("." for main repo) and the values are the
  initial_rev/startcommit

* the extractPatches function now extracts patch for the main repo and
  for all submodules and stores them in a hierarchical way describing the
    submodule path

* store initial_rev/commit also for all submodules inside the recipe
  bbappend file

* _export_patches now returns dictionaries that contains the 'patchdir'
  parameter (if any). This parameter is used to add the correct
  'patchdir=' parameter on the recipe

Also, recipe can extract a secondary git tree inside the workdir.

By default, at the end of the do_patch function, there is a hook in
devtool that commits everything that was modified to have a clean
repository. It uses the command: "git add .; git commit ..."

The issue here is that, it adds the secondary git tree as a submodule
but in a wrong way. Doing "git add <git dir>" declares a submodule but do
not adds a url associated to it, and all following "git submodule foreach"
commands will fail.

So detect that a git tree was extracted inside S and correctly add it
using "git submodule add <url> <path>", so that it will be considered as a
regular git submodule

(From OE-Core rev: 900129cbdf25297a42ab5dbd02d1adbea405c935)

Signed-off-by: Julien Stephan <jstephan@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/lib/recipetool/append.py

@@ -299,7 +299,7 @@ def appendfile(args):
                 if st.st_mode & stat.S_IXUSR:
                     perms = '0755'
             install = {args.newfile: (args.targetpath, perms)}
-        oe.recipeutils.bbappend_recipe(rd, args.destlayer, {args.newfile: sourcepath}, install, wildcardver=args.wildcard_version, machine=args.machine)
+        oe.recipeutils.bbappend_recipe(rd, args.destlayer, {args.newfile: {'path' : sourcepath}}, install, wildcardver=args.wildcard_version, machine=args.machine)
         tinfoil.modified_files()
         return 0
     else:
@@ -353,7 +353,7 @@ def appendsrc(args, files, rd, extralines=None):
                 logger.warning('{0!r} is already in SRC_URI, not adding'.format(source_uri))
         else:
             extralines.append('SRC_URI += {0}'.format(source_uri))
-        copyfiles[newfile] = srcfile
+        copyfiles[newfile] = {'path' : srcfile}
 
     oe.recipeutils.bbappend_recipe(rd, args.destlayer, copyfiles, None, wildcardver=args.wildcard_version, machine=args.machine, extralines=extralines)
     tinfoil.modified_files()