examples: fix build dependencies
examples: fix build dependencies

When building for ARM some examples were failing to compile because
of some dependencies disabled.
Declaring these dependencies prevent from trying to compile some
not supported examples.

Signed-off-by: Thomas Monjalon <ee2fa8b2681c737f775687e475dcbf2028a412f1@6wind.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk