schema parsers CHANGE applying deviation substatements' extensions

Extension instances from the deviate's substatements must be placed
into the deviated structures. Also reverting of the deviation must
count with them.

Currently applied only to YIN parser, but ready for YANG parser.

This patch does not inlude deviating the extension instances themselves,
only the extension from the deviating statements (like mandatory, config, ...)
are cover now.
diff --git a/src/parser.h b/src/parser.h
index 78bb1a2..4cdd6a5 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -113,6 +113,7 @@
 
 void lyp_sort_revisions(struct lys_module *module);
 int lyp_rfn_apply_ext(struct lys_module *module);
+int lyp_deviation_apply_ext(struct lys_module *module);
 
 /**
  * @brief Propagate imports and includes into the main module