clock synchronization rewrite

clock synchronization mechanism rewritten to use systemd-timesync instead of NtpDate; at the moment, requires:
- modifying /etc/qubes-rpc/policy/qubes.GetDate to redirect GetDate to designated clockvm
- enabling clocksync service in clockvm ( qvm-features clockvm-name service/clocksync true )

Works as specified in issue listed below, except for:
- each VM synces with clockvm after boot and every 6h
- clockvm synces time with the Internet using systemd-timesync
- dom0 synces itself with clockvm every 1h (using cron)

fixes QubesOS/qubes-issues#1230

pm-utils/01qubes-sync-vms-clock

@@ -1,17 +0,0 @@
-#!/bin/sh
-
-sync_qubes_vms_wallclock()
-{
-    # Sync all VMs (based on dom0 clock if network time sync fails)
-    /usr/bin/qvm-sync-clock --force --verbose
-}
-
-case "$1" in
-        thaw|resume) sync_qubes_vms_wallclock ;;
-        # Kill qvm-sync-clock (if running) to not desync time after resume
-        suspend|hibernate) 
-            killall qvm-sync-clock 2> /dev/null
-            exit 0
-            ;;
-        *) exit 0 ;;
-esac

pm-utils/qubes-suspend.service

@@ -7,10 +7,8 @@ StopWhenUnneeded=yes
 Type=oneshot
 RemainAfterExit=yes
 StandardOutput=syslog
-ExecStartPre=/usr/lib64/pm-utils/sleep.d/01qubes-sync-vms-clock suspend suspend
 ExecStart=/usr/lib64/pm-utils/sleep.d/52qubes-pause-vms suspend suspend
 ExecStop=/usr/lib64/pm-utils/sleep.d/52qubes-pause-vms resume suspend
-ExecStopPost=/usr/lib64/pm-utils/sleep.d/01qubes-sync-vms-clock resume suspend
 
 [Install]
 WantedBy=sleep.target

rpm_spec/core-dom0-linux.spec

@@ -112,7 +112,6 @@ cp qrexec/qubes-rpc-multiplexer $RPM_BUILD_ROOT/usr/lib/qubes
 
 ### pm-utils
 mkdir -p $RPM_BUILD_ROOT/usr/lib64/pm-utils/sleep.d
-cp pm-utils/01qubes-sync-vms-clock $RPM_BUILD_ROOT/usr/lib64/pm-utils/sleep.d/
 cp pm-utils/52qubes-pause-vms $RPM_BUILD_ROOT/usr/lib64/pm-utils/sleep.d/
 mkdir -p $RPM_BUILD_ROOT/usr/lib/systemd/system
 cp pm-utils/qubes-suspend.service $RPM_BUILD_ROOT/usr/lib/systemd/system/
@@ -210,7 +209,6 @@ chmod -x /etc/grub.d/10_linux
 /usr/bin/qvm-move-to-vm
 /usr/lib/qubes/qfile-dom0-agent
 # pm-utils
-/usr/lib64/pm-utils/sleep.d/01qubes-sync-vms-clock
 /usr/lib64/pm-utils/sleep.d/52qubes-pause-vms
 /usr/lib/systemd/system/qubes-suspend.service
 # Others

system-config/qubes-sync-clock.cron

@@ -1 +1 @@
-*/6 * * * * root /usr/bin/qvm-sync-clock > /dev/null 2>&1 || true
+0 */1 * * * root /usr/bin/qvm-sync-clock > /dev/null 2>&1 || true