ntp: add explicit perl dependency to ntp-utils package

The ntp-utils package contains at least one perl-using script as well as
a supporting perl module, therefore we need a dependency on perl.

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Joe MacDonald <joe_macdonald@mentor.com>