at: define __isleap when needed.

srcpkgs/at/patches/isleap.patch

@@ -0,0 +1,13 @@
+--- parsetime.y.orig	2015-05-11 15:16:53.018305563 +0200
++++ parsetime.y	2015-05-11 15:17:22.820153470 +0200
+@@ -6,6 +6,10 @@
+ #include "parsetime.h"
+ #include "panic.h"
+ 
++#ifndef __isleap
++#define __isleap(year) ((year)%4 == 0 && ((year)%100 != 0 || (year)%400 == 0))
++#endif
++
+ #define YYDEBUG 1
+ 
+ struct tm exectm;

srcpkgs/at/template

@@ -1,7 +1,7 @@
 # Template file for 'at'
 pkgname=at
 version=3.1.16
-revision=1
+revision=2
 build_style=gnu-configure
 configure_args="--with-jobdir=/var/spool/atd --with-atspool=/var/spool/atd
  --sbindir=/usr/bin --with-daemon_username=at --with-daemon_groupname=at