patch 8.1.1736: viminfo support is spread out

Problem:    Viminfo support is spread out.
Solution:   Move more viminfo code to viminfo.c. (Yegappan Lakshmanan,
            closes #4717)  Reorder code to make most functions static.
diff --git a/src/proto/search.pro b/src/proto/search.pro
index eb614a1..143333d 100644
--- a/src/proto/search.pro
+++ b/src/proto/search.pro
@@ -46,6 +46,6 @@
 int current_search(long count, int forward);
 int linewhite(linenr_T lnum);
 void find_pattern_in_path(char_u *ptr, int dir, int len, int whole, int skip_comments, int type, long count, int action, linenr_T start_lnum, linenr_T end_lnum);
-int read_viminfo_search_pattern(vir_T *virp, int force);
-void write_viminfo_search_pattern(FILE *fp);
+struct spat *get_spat(int idx);
+int get_spat_last_idx(void);
 /* vim: set ft=c : */