variants: opta/portenta add fs flash

[gibix]

No description provided.

[github-actions]

Built 0.53.2-0.dev+f386c9d0

CI run PASSED 🟢

Artifact	Board	Core	Tests	RAM	Sketches	Warnings	Errors
✅ zephyr_contrib	ek_ra8d1	📗	✅	11.9%	2	-	-
	frdm_mcxn947	3 🏷️	✅	58.0%	2	-	-
	frdm_rw612	1 🏷️	✅	83.0%	2	-	-
✔️* zephyr_main	giga	4 🏷️	✅*	54.5%	44	8	-
	nano33ble	1 🏷️	✅*	78.7%	22	8	-
	nano_matter	📗	✔️*	⚠️ 85.7%	20	8	(2*)
	niclasense	2 🏷️	✅*	⚠️ 87.3%	20	8	-
	opta	4 🏷️	✅*	56.5%	54	8	-
	portentac33	3 🏷️	✔️*	⚠️ 95.1%	56	8	(8*)
	portentah7	3 🏷️	✅*	57.1%	58	8	-
✅* zephyr_unoq	unoq	📗	✅*	26.4%	60	8	-

Legend

Board	Test	Status description
🔥	🔥	Test run failed to complete.
❌	🔴	Test completed with unexpected errors.
✔️*	🚫	Test completed with errors, but all are known/expected.
✅*	🟡	Test completed with some warnings; no errors detected.
✅	🟢	Test passed successfully, with no warnings or errors.
🌑	🌑	Test was skipped.

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