Change OpenWRT's DHCP lease time to 2m

To prevent `no address available` error from DHCP of OpenWRT

Bug: 275044135
Test: When a phone is connected to WiFi, OpenWRT shows dhcp lease time
      as 2m.
(cherry picked from https://android-review.googlesource.com/q/commit:66676e274a212ea7e21bd24259940c6a9f7efa5b)
Merged-In: Ie78bf6e05afa3ee4bafc42f5957a40180b690b5c
Change-Id: Ie78bf6e05afa3ee4bafc42f5957a40180b690b5c
1 file changed