Generate a random number for DHCPv6 message retransmission algorithm.

Per RFC8415 section15 a randomization factor is needed to compute
the Retransmission Timeout, a random number chosen with a uniform
distribution between -0.1 and +0.1.

Bug: 260934173
Test: TH
Change-Id: Ided335925a2a68fc2b420f7accbc8043147aa3ea
1 file changed