Ports: Update mandoc's patches to use git patches

Ports/mandoc/patches/0005-Use-pcre2-for-regex.patch

@@ -0,0 +1,25 @@
+From 7c8e432900e1aafc14d7012cb1456b55c5db860a Mon Sep 17 00:00:00 2001
+From: Brian Callahan <bcallah@openbsd.org>
+Date: Sat, 25 Jan 2020 21:20:39 -0500
+Subject: [PATCH 5/9] Use pcre2 for regex
+
+---
+ dbm_map.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/dbm_map.c b/dbm_map.c
+index 87c085d..d5c620e 100644
+--- a/dbm_map.c
++++ b/dbm_map.c
+@@ -36,7 +36,7 @@
+ #endif
+ #include <errno.h>
+ #include <fcntl.h>
+-#include <regex.h>
++#include <pcre2posix.h>
+ #include <stdint.h>
+ #include <stdlib.h>
+ #include <string.h>
+-- 
+2.36.1
+