patch 8.0.1564: too many #ifdefs

Problem:    Too many #ifdefs.
Solution:   Graduate the +autocmd feature. Takes away 450 #ifdefs and
            increases code size of tiny Vim by only 40 Kbyte.
diff --git a/src/search.c b/src/search.c
index d3c6518..a4b2722 100644
--- a/src/search.c
+++ b/src/search.c
@@ -97,10 +97,8 @@
 static int	lastc_bytelen = 1;	/* >1 for multi-byte char */
 #endif
 
-#if defined(FEAT_AUTOCMD) || defined(FEAT_EVAL) || defined(PROTO)
 /* copy of spats[], for keeping the search patterns while executing autocmds */
 static struct spat  saved_spats[2];
-#endif
 # ifdef FEAT_SEARCH_EXTRA
 /* copy of spats[RE_SEARCH], for keeping the search patterns while incremental
  * searching */
@@ -300,7 +298,6 @@
     }
 }
 
-#if defined(FEAT_AUTOCMD) || defined(FEAT_EVAL) || defined(PROTO)
 /*
  * Save the search patterns, so they can be restored later.
  * Used before/after executing autocommands and user functions.
@@ -318,10 +315,10 @@
 	saved_spats[1] = spats[1];
 	if (spats[1].pat != NULL)
 	    saved_spats[1].pat = vim_strsave(spats[1].pat);
+#ifdef FEAT_SEARCH_EXTRA
 	saved_last_idx = last_idx;
-# ifdef FEAT_SEARCH_EXTRA
 	saved_no_hlsearch = no_hlsearch;
-# endif
+#endif
     }
 }
 
@@ -332,18 +329,17 @@
     {
 	vim_free(spats[0].pat);
 	spats[0] = saved_spats[0];
-# if defined(FEAT_EVAL)
+#if defined(FEAT_EVAL)
 	set_vv_searchforward();
-# endif
+#endif
 	vim_free(spats[1].pat);
 	spats[1] = saved_spats[1];
+#ifdef FEAT_SEARCH_EXTRA
 	last_idx = saved_last_idx;
-# ifdef FEAT_SEARCH_EXTRA
 	SET_NO_HLSEARCH(saved_no_hlsearch);
-# endif
+#endif
     }
 }
-#endif
 
 #if defined(EXITFREE) || defined(PROTO)
     void