Plane:remove stale conversion code #45334

Job	Run time
build (stm32f7, chibios, 10)	13m 35s
build (stm32h7, chibios, 10)	12m 14s
build (fmuv2-plane, chibios, 10)	5m 46s
build (periph-build, chibios, 10)	14m 32s
build (iofirmware, chibios, 10)	2m 33s
build (CubeOrange-bootloader, chibios, 10)	1m 10s
build (fmuv3-bootloader, chibios, 10)	1m 15s
build (revo-bootloader, chibios, 10)	1m 7s
build (stm32h7-debug, chibios, 10)	7m 10s
build (fmuv3, chibios, 10)	13m 55s
build (revo-mini, chibios, 10)	10m 30s
build (MatekF405-Wing, chibios, 10)	11m 47s
build (CubeOrange-ODID, chibios, 10)	8m 21s
build (CubeRedPrimary-bootloader, chibios, 10)	1m 9s
build (configure-all, chibios, 10)	11m 36s
build (build-options-defaults-test, chibios, 10)	24m 1s
build (signing, chibios, 10)	9m 4s
build (CubeOrange-PPP, chibios, 10)	7m 15s
build (CubeRed-EKF2, chibios, 10)	6m 39s
build (SOHW, chibios, 10)	11m 11s
build (Pixhawk6X-PPPGW, chibios, 10)	3m 28s
build (new-check, chibios, 10)	13m 31s
	3h 11m 49s

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