imperxflexsrc: support packed pixel formats

Since we're using the Imperx unpack function, we can easily handle
packed pixel formats. For performance reasons, we could always support
packed pixel formats directly by adding new caps.

sys/imperxflex/gstframelinksrc.c

@@ -356,9 +356,7 @@ gst_framelinksrc_start (GstBaseSrc * bsrc)
   memcpy (&src->pixInfo, &camConfig.pixelInfo, sizeof (VCECLB_RawPixelInfoEx));
 
   if (ci->Packed == 1) {
-    GST_ELEMENT_ERROR (src, RESOURCE, SETTINGS,
-        ("Packed pixel data not supported yet."), (NULL));
-    return FALSE;
+    GST_LOG_OBJECT (src, "Pixel data is packed, we'll unpack it");
   }
 
   /* enumerate devices */