bitbake: hob: changes to INHERIT var should use "append" operation

Setting INHERIT var means to remove other operations made on INHERIT.
This is too intrusive, so we decided to use append for this case.

[YOCTO #5448]
(Bitbake rev: a2d0122c198ee50325e6f0e2f5d1c2284475fc7b)

Signed-off-by: Cristiana Voicu <cristiana.voicu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/ui/crumbs/hobeventhandler.py

@@ -306,9 +306,7 @@ class HobHandler(gobject.GObject):
         self.runCommand(["createConfigFile", ".hob.conf"])
 
     def set_extra_inherit(self, bbclass):
-        inherits = self.runCommand(["getVariable", "INHERIT"]) or ""
-        inherits = inherits + " " + bbclass
-        self.set_var_in_file("INHERIT", inherits, ".hob.conf")
+        self.append_var_in_file("INHERIT", bbclass, ".hob.conf")
 
     def set_bblayers(self, bblayers):
         self.set_var_in_file("BBLAYERS", " ".join(bblayers), "bblayers.conf")