BUILD: enable build on Linux/s390x

I would like to contribute the following fix to enable the Linux s390x
platform. The fix was built against today's git master. I've attached the
patch for review. Depending on your buildbot/jenkins/? requirements I can
set up a virtual machine for automated building/testing of the package in
this environment.
(cherry picked from commit 5e98e3e99876725988c5da588b43ad9c3015a24c)
diff --git a/include/common/syscall.h b/include/common/syscall.h
index 7c9a456..9554d5a 100644
--- a/include/common/syscall.h
+++ b/include/common/syscall.h
@@ -104,6 +104,10 @@
 #define __NR_epoll_create 254
 #define __NR_epoll_ctl    255
 #define __NR_epoll_wait   256
+#elif defined (__s390__) || defined(__s390x__)
+#define __NR_epoll_create 249
+#define __NR_epoll_ctl    250
+#define __NR_epoll_wait   251
 #endif /* $arch */
 #endif /* __NR_epoll_ctl */
 
@@ -121,6 +125,8 @@
 #define __NR_splice             468
 #elif defined (__i386__)
 #define __NR_splice             313
+#elif defined(__s390__) || defined(__s390x__)
+#define __NR_splace		306
 #endif /* $arch */
 #endif /* __NR_splice */