net/sniproxy: remove useless patch

Since STAILQ_* has been added to base queue.h
(https://marc.info/?l=openbsd-cvs&m=160933521301472&w=2) there is no need to
patch net/sniproxy.

Index: patch-src_backend_h
===================================================================
RCS file: patch-src_backend_h
diff -N patch-src_backend_h
--- patch-src_backend_h 8 Apr 2020 04:56:52 -0000 1.1.1.1
+++ /dev/null 1 Jan 1970 00:00:00 -0000
@@ -1,95 +0,0 @@
-$OpenBSD: patch-src_backend_h,v 1.1.1.1 2020/04/08 04:56:52 bket Exp $
-
-Index: src/backend.h
---- src/backend.h.orig
-+++ src/backend.h
-@@ -31,6 +31,89 @@
- #include <pcre.h>
- #include "address.h"
-
-+#ifndef STAILQ_INIT
-+/*
-+ * Singly-linked Tail queue declarations.
-+ */
-+#define STAILQ_HEAD(name, type) \
-+struct name { \
-+ struct type *stqh_first; /* first element */ \
-+ struct type **stqh_last; /* addr of last next element */ \
-+}
-+
-+#define STAILQ_HEAD_INITIALIZER(head) \
-+ { NULL, &(head).stqh_first }
-+
-+#define STAILQ_ENTRY(type) \
-+struct { \
-+ struct type *stqe_next; /* next element */ \
-+}
-+
-+/*
-+ * Singly-linked Tail queue functions.
-+ */
-+#define STAILQ_INIT(head) do { \
-+ (head)->stqh_first = NULL; \
-+ (head)->stqh_last = &(head)->stqh_first; \
-+} while (/*CONSTCOND*/0)
-+
-+#define STAILQ_INSERT_HEAD(head, elm, field) do { \
-+ if (((elm)->field.stqe_next = (head)->stqh_first) == NULL) \
-+ (head)->stqh_last = &(elm)->field.stqe_next; \
-+ (head)->stqh_first = (elm); \
-+} while (/*CONSTCOND*/0)
-+
-+#define STAILQ_INSERT_TAIL(head, elm, field) do { \
-+ (elm)->field.stqe_next = NULL; \
-+ *(head)->stqh_last = (elm); \
-+ (head)->stqh_last = &(elm)->field.stqe_next; \
-+} while (/*CONSTCOND*/0)
-+
-+#define STAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
-+ if (((elm)->field.stqe_next = (listelm)->field.stqe_next) == NULL)\
-+ (head)->stqh_last = &(elm)->field.stqe_next; \
-+ (listelm)->field.stqe_next = (elm); \
-+} while (/*CONSTCOND*/0)
-+
-+#define STAILQ_REMOVE_HEAD(head, field) do { \
-+ if (((head)->stqh_first = (head)->stqh_first->field.stqe_next) == NULL) \
-+ (head)->stqh_last = &(head)->stqh_first; \
-+} while (/*CONSTCOND*/0)
-+
-+#define STAILQ_REMOVE(head, elm, type, field) do { \
-+ if ((head)->stqh_first == (elm)) { \
-+ STAILQ_REMOVE_HEAD((head), field); \
-+ } else { \
-+ struct type *curelm = (head)->stqh_first; \
-+ while (curelm->field.stqe_next != (elm)) \
-+ curelm = curelm->field.stqe_next; \
-+ if ((curelm->field.stqe_next = \
-+ curelm->field.stqe_next->field.stqe_next) == NULL) \
-+ (head)->stqh_last = &(curelm)->field.stqe_next; \
-+ } \
-+} while (/*CONSTCOND*/0)
-+
-+#define STAILQ_FOREACH(var, head, field) \
-+ for ((var) = ((head)->stqh_first); \
-+ (var); \
-+ (var) = ((var)->field.stqe_next))
-+
-+#define STAILQ_CONCAT(head1, head2) do { \
-+ if (!STAILQ_EMPTY((head2))) { \
-+ *(head1)->stqh_last = (head2)->stqh_first; \
-+ (head1)->stqh_last = (head2)->stqh_last; \
-+ STAILQ_INIT((head2)); \
-+ } \
-+} while (/*CONSTCOND*/0)
-+
-+/*
-+ * Singly-linked Tail queue access methods.
-+ */
-+#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL)
-+#define STAILQ_FIRST(head) ((head)->stqh_first)
-+#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next)
-+