tests: Increase retry limit and timeout for wpas_mesh_open_no_auto

tests: Increase retry limit and timeout for wpas_mesh_open_no_auto

This test case was failing every now and then due to dev1
(no_auto_peer=1) not receiving the new-peer-candidate event in time
before dev0 has already stopped retries on mesh peering open message.
This sounds somewhat expected with the default 4 * 40 ms = 160 ms
retries and 1000 TU beacon interval. Use maximum timeout 16 * 255 ms =
4080 ms to make this test case less likely to fail.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>