opensmtpd: fix realpath() on glibc with FORTIFY_SOURCE.

PATH_MAX must be at least 4096, otherwise glibc will abort because it
thinks there's a buffer overflow if it's compiled with _FORTIFY_SOURCE.

srcpkgs/opensmtpd/patches/glibc-fortify-source-path-max.patch

@@ -0,0 +1,18 @@
+Don't override PATH_MAX, glibc with FORTIFY_SOURCE exactly wants
+it as 4096 bytes at least, otherwise it will abort().
+
+	-- xtraeme
+
+--- openbsd-compat/defines.h.orig	2015-04-01 12:25:34.304411927 +0200
++++ openbsd-compat/defines.h	2015-04-01 12:26:10.832810710 +0200
+@@ -65,10 +65,6 @@ enum
+  * Looks like ugly, but MAX_IMSGSIZE equals 16384,
+  * and if we don't care it will overflow for some struct
+  */
+-#if PATH_MAX > 1024
+-#  undef  PATH_MAX
+-#  define PATH_MAX 1024
+-#endif
+ 
+ #if MAXPATHLEN > 1024
+ #  undef  MAXPATHLEN

srcpkgs/opensmtpd/template

@@ -1,7 +1,7 @@
 # Template file for 'opensmtpd'
 pkgname=opensmtpd
 version=5.4.4p1
-revision=7
+revision=8
 build_style=gnu-configure
 configure_args="--sysconfdir=/etc/smtpd --sbindir=/usr/sbin
  --with-maildir=/var/spool/mail --with-privsep-path=/var/db