chrony: fix build failure for arma9
    
    Eliminate references to syscalls not available
    for ARM_EABI.  Also add a dependency on libseccomp
    which is needed for scfilter to work.
    
    Set PACKAGECONFIG to not enable scfilter, since
    kernel CONFIG_SECCOMP is unlikely to be set.  This
    aligns the usage of libseccomp with that of other packages.

    Upstream-Status: Pending
    
    Signed-off-by: Joe Slater <jslater@windriver.com>

--- a/sys_linux.c
+++ b/sys_linux.c
@@ -453,13 +453,12 @@ SYS_Linux_EnableSystemCallFilter(int lev
   const int syscalls[] = {
     /* Clock */
     SCMP_SYS(adjtimex), SCMP_SYS(gettimeofday), SCMP_SYS(settimeofday),
-    SCMP_SYS(time),
     /* Process */
-    SCMP_SYS(clone), SCMP_SYS(exit), SCMP_SYS(exit_group), SCMP_SYS(getrlimit),
+    SCMP_SYS(clone), SCMP_SYS(exit), SCMP_SYS(exit_group),
     SCMP_SYS(rt_sigaction), SCMP_SYS(rt_sigreturn), SCMP_SYS(rt_sigprocmask),
     SCMP_SYS(set_tid_address), SCMP_SYS(sigreturn), SCMP_SYS(wait4),
     /* Memory */
-    SCMP_SYS(brk), SCMP_SYS(madvise), SCMP_SYS(mmap), SCMP_SYS(mmap2),
+    SCMP_SYS(brk), SCMP_SYS(madvise), SCMP_SYS(mmap2),
     SCMP_SYS(mprotect), SCMP_SYS(mremap), SCMP_SYS(munmap), SCMP_SYS(shmdt),
     /* Filesystem */
     SCMP_SYS(access), SCMP_SYS(chmod), SCMP_SYS(chown), SCMP_SYS(chown32),
@@ -470,14 +469,21 @@ SYS_Linux_EnableSystemCallFilter(int lev
     SCMP_SYS(bind), SCMP_SYS(connect), SCMP_SYS(getsockname),
     SCMP_SYS(recvfrom), SCMP_SYS(recvmsg), SCMP_SYS(sendmmsg),
     SCMP_SYS(sendmsg), SCMP_SYS(sendto),
-    /* TODO: check socketcall arguments */
-    SCMP_SYS(socketcall),
     /* General I/O */
     SCMP_SYS(_newselect), SCMP_SYS(close), SCMP_SYS(open), SCMP_SYS(pipe),
-    SCMP_SYS(poll), SCMP_SYS(read), SCMP_SYS(futex), SCMP_SYS(select),
+    SCMP_SYS(poll), SCMP_SYS(read), SCMP_SYS(futex),
     SCMP_SYS(set_robust_list), SCMP_SYS(write),
     /* Miscellaneous */
     SCMP_SYS(uname),
+    /* not always available */
+#if ! defined(__ARM_EABI__)
+    SCMP_SYS(time),
+    SCMP_SYS(getrlimit),
+    SCMP_SYS(select),
+    SCMP_SYS(mmap),
+    /* TODO: check socketcall arguments */
+    SCMP_SYS(socketcall),
+#endif
   };
 
   const int socket_domains[] = {