update operator initContainer and vfioManager images to 12.6.0 #401

Job	Run time
helm-lint	8s
validate-helm-values	30s
validate-csv	30s
go-check	1m 42s
unit tests	54s
go-build	1m 39s
build-gpu-operator (ubi8)	13m 6s
build-gpu-operator-validator (ubi8)	10m 5s
e2e-tests-containerd	51m 44s
e2e-tests-nvidiadriver	31m 50s
	1h 52m 8s

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