Revert "ostbuild: Check for the Makefile in the correct directory"

I'm not sure how this made anything work...probably I was screwing
something else up.

This reverts commit aeeed8da13.

src/ostbuild/pyostbuild/builtin_compile_one.py

@@ -152,10 +152,7 @@ class OstbuildCompileOne(builtins.Builtin):
         args.extend(self.configargs)
         run_sync(args, cwd=builddir)
 
-        if use_builddir:
         makefile_path = os.path.join(builddir, 'Makefile')
-        else:
-            makefile_path = 'Makefile'
         if not os.path.exists(makefile_path):
             fatal("No Makefile found")