AC_PosControl: lthall fixes #3516

Job	Run time
build (stm32f7, chibios, 10)	10m 1s
build (stm32h7, chibios, 10)	8m 59s
build (fmuv2-plane, chibios, 10)	5m 22s
build (periph-build, chibios, 10)	5m 32s
build (iofirmware, chibios, 10)	3m 32s
build (CubeOrange-bootloader, chibios, 10)	2m 56s
build (fmuv3-bootloader, chibios, 10)	3m 2s
build (revo-bootloader, chibios, 10)	3m 2s
build (stm32h7-debug, chibios, 10)	6m 13s
build (fmuv3, chibios, 10)	12m 18s
build (revo-mini, chibios, 10)	9m 55s
build (MatekF405-Wing, chibios, 10)	10m 40s
build (CubeOrange-ODID, chibios, 10)	7m 19s
build (CubeRedPrimary-bootloader, chibios, 10)	3m 11s
build (configure-all, chibios, 10)	12m 53s
build (build-options-defaults-test, chibios, 10)	15m 41s
build (signing, chibios, 10)	6m 34s
build (CubeOrange-PPP, chibios, 10)	6m 11s
build (CubeRed-EKF2, chibios, 10)	5m 55s
build (SOHW, chibios, 10)	9m 2s
build (Pixhawk6X-PPPGW, chibios, 10)	3m 18s
build (new-check, chibios, 10)	10m 50s
	2h 42m 26s

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