runqemu: use realpath for imgdir

The DEPLOY_DIR_IMAGE maybe relative or absolute path since it can be
read from env vars, so use realpath for both imgdir and
DEPLOY_DIR_IMAGE when compare.

(From OE-Core rev: dad9f27278850d0d3818344fea877835632576cb)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/runqemu

@@ -693,8 +693,8 @@ class BaseConfig(object):
         # artefacts are relative to that file, rather than in whatever
         # directory DEPLOY_DIR_IMAGE in the conf file points to.
         if self.qbconfload:
-            imgdir = os.path.dirname(self.qemuboot)
-            if imgdir != self.get('DEPLOY_DIR_IMAGE'):
+            imgdir = os.path.realpath(os.path.dirname(self.qemuboot))
+            if imgdir != os.path.realpath(self.get('DEPLOY_DIR_IMAGE')):
                 logger.info('Setting DEPLOY_DIR_IMAGE to folder containing %s (%s)' % (self.qemuboot, imgdir))
                 self.set('DEPLOY_DIR_IMAGE', imgdir)