GPO: Allow customization of GPO_CROND per OS

For both Debian and Ubuntu, the cron PAM service is named "cron" instead
of "crond", denying the use of the service by default.

This patch enables the HAVE_$OS (HAVE_DEBIAN/HAVE_FEDORA...) macros to select
the service name during build, allowing further customization if required.

Resolves:
https://bugs.launchpad.net/ubuntu/+source/sssd/+bug/1572908

Reviewed-by: Michal Židek <mzidek@redhat.com>

src/external/platform.m4

@@ -36,6 +36,14 @@ AM_CONDITIONAL([HAVE_SUSE], [test x"$osname" = xsuse])
 AM_CONDITIONAL([HAVE_DEBIAN], [test x"$osname" = xdebian])
 AM_CONDITIONAL([HAVE_GENTOO], [test x"$osname" = xgentoo])
 
+AS_CASE([$osname],
+        [redhat], [AC_DEFINE_UNQUOTED([HAVE_REDHAT], 1, [Build with redhat config])],
+        [fedora], [AC_DEFINE_UNQUOTED([HAVE_FEDORA], 1, [Build with fedora config])],
+        [suse], [AC_DEFINE_UNQUOTED([HAVE_SUSE], 1, [Build with suse config])],
+        [gentoo], [AC_DEFINE_UNQUOTED([HAVE_GENTOO], 1, [Build with gentoo config])],
+        [debian], [AC_DEFINE_UNQUOTED([HAVE_DEBIAN], 1, [Build with debian config])],
+        [AC_MSG_NOTICE([Build with $osname config])])
+
 AC_CHECK_MEMBERS([struct ucred.pid, struct ucred.uid, struct ucred.gid], , ,
                  [[#include <sys/socket.h>]])
 

src/providers/ad/ad_gpo.c

@@ -200,7 +200,11 @@ int ad_gpo_process_cse_recv(struct tevent_req *req);
 #define GPO_SSHD "sshd"
 #define GPO_FTP "ftp"
 #define GPO_SAMBA "samba"
+#ifdef HAVE_DEBIAN
+#define GPO_CROND "cron"
+#else
 #define GPO_CROND "crond"
+#endif
 #define GPO_POLKIT "polkit-1"
 #define GPO_SUDO "sudo"
 #define GPO_SUDO_I "sudo-i"