Support mtu_request for OVS

[rollandf]

For using non-default MTU, OVS supports "mtu_request" field when adding a port to the bridge.

eg:
https://docs.openvswitch.org/en/latest/topics/dpdk/jumbo-frames/

[github-actions]

Thanks for your PR,
To run vendors CIs, Maintainers can use one of:

• /test-all: To run all tests for all vendors.
• /test-e2e-all: To run all E2E tests for all vendors.
• /test-e2e-nvidia-all: To run all E2E tests for NVIDIA vendor.

To skip the vendors CIs, Maintainers can use one of:

• /skip-all: To skip all tests for all vendors.
• /skip-e2e-all: To skip all E2E tests for all vendors.
• /skip-e2e-nvidia-all: To skip all E2E tests for NVIDIA vendor.
  Best regards.

[rollandf]

@ykulazhenkov PTAL

[coveralls]

Pull Request Test Coverage Report for Build 12670776895

Details

• 8 of 15 (53.33%) changed or added relevant lines in 3 files are covered.
• 5 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.007%) to 47.399%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
api/v1/helper.go	2	4	50.0%
api/v1/zz_generated.deepcopy.go	0	5	0.0%

Files with Coverage Reduction	New Missed Lines	%
api/v1/helper.go	1	75.83%
controllers/helper.go	1	69.66%
controllers/drain_controller.go	3	78.57%

Totals
Change from base Build 12586487060:	-0.007%
Covered Lines:	7262
Relevant Lines:	15321

---

💛 - Coveralls

[ykulazhenkov]

LGTM

[rollandf]

@SchSeba @zeeke PTAL when you have time

[zeeke]

LGTM