acl: fix division by float zero in test app

acl: fix division by float zero in test app

Fix issue reported by Coverity.
Coverity ID 13240

This could cause an immediate crash or incorrect computation.

In search_ip5tuples: An expression which may be zero is used
as a divisor in floating-point arithmetic.

divide_by_zero: In expression (long double)tm / pkt,
division by expression pkt which may be zero has undefined behavior.

Fixes: 26c057ab6c45 ("acl: new test-acl application")

Signed-off-by: Daniel Mrzyglod <danielx.t.mrzyglod@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>