postfix: version update to 3.1.0

Signed-off-by: Denis Shulyaka <Shulyaka@gmail.com>

mail/postfix/patches/500-crosscompile.patch

@@ -1,6 +1,6 @@
 --- a/makedefs	2016-01-28 12:30:14.444082390 -0500
 +++ b/makedefs	2016-01-28 13:44:02.092006512 -0500
-@@ -193,7 +193,7 @@ error() {
+@@ -198,7 +198,7 @@ error() {
  
  case $# in
   # Officially supported usage.
@@ -9,7 +9,7 @@
      RELEASE=`(uname -r) 2>/dev/null`
      # No ${x%%y} support in Solaris 11 /bin/sh
      RELEASE_MAJOR=`expr "$RELEASE" : '\([0-9]*\)'` || exit 1
-@@ -207,6 +207,15 @@ case $# in
+@@ -212,6 +212,15 @@ case $# in
  esac
  
  case "$SYSTEM.$RELEASE" in