[wlan e2e] Support OpenWRT for Dhcpv4InteropBasicTest

Update the DHCP end-to-end interoperability tests to support OpenWrt
access points alongside existing controllers. This change introduces
OpenWrt-specific DHCP configuration logic and log normalization to
ensure compatibility with existing test assertions.

Bug: 500981378
Test: fx test --build --e2e --output //src/testing/end_to_end/antlion/tests/dhcp:dhcpv4_interop_basic_test
Change-Id: I3a577144b949f2d20a750fa60a47b4f092a997c7
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1569853
Commit-Queue: Vison Li <visonli@google.com>
Fuchsia-Auto-Submit: Vison Li <visonli@google.com>
Reviewed-by: Charles Celerier <chcl@google.com>
6 files changed