Install ntp packages to fix issue on cloudera manager agent installation

Install ntp packages to fix issue on cloudera manager agent installation (RHEL7: yum install ntp)

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18/Mar/2018 10:40:32 +0000] 6339 MainThread agent        INFO     Active parcel list updated; recalculating component info.
[18/Mar/2018 10:40:33 +0000] 6339 MainThread throttling_logger INFO     Identified java component java8 with full version JAVA_HOME=/usr/java/defa
ult java version "1.8.0_162" Java(TM) SE Runtime Environment (build 1.8.0_162-b12) Java HotSpot(TM) 64-Bit Server VM (build 25.162-b12, mixed mode
)  for requested version misc.
[18/Mar/2018 10:40:33 +0000] 6339 MainThread throttling_logger INFO     Identified java component java8 with full version JAVA_HOME=/usr/java/jdk1
.8.0_162 java version "1.8.0_162" Java(TM) SE Runtime Environment (build 1.8.0_162-b12) Java HotSpot(TM) 64-Bit Server VM (build 25.162-b12, mixed
 mode)  for requested version 8.
[18/Mar/2018 10:40:35 +0000] 6339 Monitor-HostMonitor throttling_logger ERROR    Failed to collect NTP metrics
Traceback (most recent call last):
  File "/usr/lib64/cmf/agent/build/env/lib/python2.7/site-packages/cmf-5.14.1-py2.7.egg/cmf/monitor/host/ntp_monitor.py", line 48, in collect
    self.collect_ntpd()
  File "/usr/lib64/cmf/agent/build/env/lib/python2.7/site-packages/cmf-5.14.1-py2.7.egg/cmf/monitor/host/ntp_monitor.py", line 66, in collect_ntpd
    result, stdout, stderr = self._subprocess_with_timeout(args, self._timeout)
  File "/usr/lib64/cmf/agent/build/env/lib/python2.7/site-packages/cmf-5.14.1-py2.7.egg/cmf/monitor/host/ntp_monitor.py", line 38, in _subprocess_
with_timeout
    return subprocess_with_timeout(args, timeout)
  File "/usr/lib64/cmf/agent/build/env/lib/python2.7/site-packages/cmf-5.14.1-py2.7.egg/cmf/subprocess_timeout.py", line 49, in subprocess_with_ti
meout
    p = subprocess.Popen(**kwargs)
  File "/usr/lib64/python2.7/subprocess.py", line 711, in __init__
    errread, errwrite)
  File "/usr/lib64/python2.7/subprocess.py", line 1327, in _execute_child
    raise child_exception
OSError: [Errno 2] No such file or directory