[show] Add ntpstat output to show ntp (sonic-net#861)

Signed-off-by: yangshiping <yangshiping@jd.com>

Author: yangshp1987

doc/Command-Reference.md

@@ -3997,12 +3997,17 @@ This command displays a list of NTP peers known to the server as well as a summa
 - Example:
   ```
   admin@sonic:~$ show ntp
+  synchronised to NTP server (204.2.134.164) at stratum 3
+     time correct to within 326797 ms
+     polling server every 1024 s
+
        remote           refid      st t when poll reach   delay   offset  jitter
   ==============================================================================
    23.92.29.245    .XFAC.          16 u    - 1024    0    0.000    0.000   0.000
   *204.2.134.164   46.233.231.73    2 u  916 1024  377    3.079    0.394   0.128
   ```
 
+
 ### NTP Config Commands
 
 This sub-section of commands is used to add or remove the configured NTP servers.

show/main.py

@@ -2028,20 +2028,22 @@ def bgp(verbose):
 @click.option('--verbose', is_flag=True, help="Enable verbose output")
 def ntp(ctx, verbose):
     """Show NTP information"""
+    ntpstat_cmd = "ntpstat"
     ntpcmd = "ntpq -p -n"
     if is_mgmt_vrf_enabled(ctx) is True:
         #ManagementVRF is enabled. Call ntpq using "ip vrf exec" or cgexec based on linux version 
         os_info =  os.uname()
         release = os_info[2].split('-')
         if parse_version(release[0]) > parse_version("4.9.0"):
-            ntpcmd = "ip vrf exec mgmt ntpq -p -n"
+            ntpstat_cmd = "sudo ip vrf exec mgmt ntpstat"
+            ntpcmd = "sudo ip vrf exec mgmt ntpq -p -n"
         else:
-            ntpcmd = "cgexec -g l3mdev:mgmt ntpq -p -n"
+            ntpstat_cmd = "sudo cgexec -g l3mdev:mgmt ntpstat"
+            ntpcmd = "sudo cgexec -g l3mdev:mgmt ntpq -p -n"
 
+    run_command(ntpstat_cmd, display_cmd=verbose)
     run_command(ntpcmd, display_cmd=verbose)
 
-
-
 #
 # 'uptime' command ("show uptime")
 #