wic: move wks parsing code to KickStart._parse

This is a preparation for implementation of include statement.
Parser will be called recursively to parse included .wks files,
so it should be available as a method.

(From OE-Core rev: 7778b9851758f4f782cb5f5d5fb36e68aed3b275)

Signed-off-by: Ed Bartosh <ed.bartosh@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/lib/wic/ksparser.py

@@ -115,6 +115,9 @@ class KickStart(object):
         bootloader.add_argument('--timeout', type=int)
         bootloader.add_argument('--source')
 
+        self._parse(parser, confpath)
+
+    def _parse(self, parser, confpath):
         with open(confpath) as conf:
             lineno = 0
             for line in conf: