patch 9.0.0256: compiler warning for uninitialized variables

Problem:    Compiler warning for uninitialized variables.
Solution:   Initilize the variables.

src/scriptfile.c

@@ -1358,14 +1358,14 @@ do_source_ext(
     source_cookie_T	    cookie;
     char_u		    *p;
     char_u		    *fname_not_fixed = NULL;
-    char_u		    *fname_exp;
+    char_u		    *fname_exp = NULL;
     char_u		    *firstline = NULL;
     int			    retval = FAIL;
     sctx_T		    save_current_sctx;
 #ifdef FEAT_EVAL
     funccal_entry_T	    funccalp_entry;
     int			    save_debug_break_level = debug_break_level;
-    int			    sid;
+    int			    sid = -1;
     scriptitem_T	    *si = NULL;
     int			    save_estack_compiling = estack_compiling;
     ESTACK_CHECK_DECLARATION

src/version.c

@@ -731,6 +731,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    256,
 /**/
     255,
 /**/