swupdate_class: depend on do_build of images

The do_populate_sysroot task completes before images are created in
the deploy directory, so depending on this lets do_swuimage run too
soon.  Since do_build is supposed to be the last task, depending on
it instead ensures everything has finished before we run.

Signed-off-by: Mans Rullgard <mans@mansr.com>

classes/swupdate.bbclass

@@ -61,7 +61,7 @@ def swupdate_getdepends(d):
 
     depstr = ""
     for dep in deps:
-        depstr += " " + dep + ":do_populate_sysroot"
+        depstr += " " + dep + ":do_build"
     return depstr
 
 do_swuimage[dirs] = "${TOPDIR}"