Ports: Use GNU patch instead of the OpenBSD version

The OpenBSD version is having some weird issues, so:

Reject OpenBSD, return to GNU.

Ports/patch/patches/fix-config-sub.patch

@@ -0,0 +1,12 @@
+diff -ur a/build-aux/config.sub b/build-aux/config.sub
+--- a/build-aux/config.sub	2018-02-03 13:41:53.000000000 +0100
++++ b/build-aux/config.sub	2021-11-10 01:22:51.034188104 +0100
+@@ -1363,7 +1363,7 @@
+ 	# The portable systems comes first.
+ 	# Each alternative MUST end in a * to match a version number.
+ 	# -sysv* is not here because it comes later, after sysvr4.
+-	-gnu* | -bsd* | -mach* | -minix* | -genix* | -ultrix* | -irix* \
++	-gnu* | -bsd* | -mach* | -minix* | -genix* | -ultrix* | -serenity* | -irix* \
+ 	      | -*vms* | -sco* | -esix* | -isc* | -aix* | -cnk* | -sunos | -sunos[34]*\
+ 	      | -hpux* | -unos* | -osf* | -luna* | -dgux* | -auroraux* | -solaris* \
+ 	      | -sym* | -kopensolaris* | -plan9* \

Ports/patch/patches/remove-oversized-dirfd-cache.patch

@@ -0,0 +1,14 @@
+diff -ur a/src/safe.c b/src/safe.c
+--- a/src/safe.c	2018-02-03 13:41:49.000000000 +0100
++++ b/src/safe.c	2021-11-10 02:05:04.152449983 +0100
+@@ -98,9 +98,7 @@
+ {
+   struct rlimit nofile;
+ 
+-  max_cached_fds = 8;
+-  if (getrlimit (RLIMIT_NOFILE, &nofile) == 0)
+-    max_cached_fds = MAX (nofile.rlim_cur / 4, max_cached_fds);
++  max_cached_fds = 64;
+ 
+   cached_dirfds = hash_initialize (max_cached_fds,
+ 				   NULL,