AP_InertialSensor: tidy IMU killing #40040

Job	Run time
build (stm32f7, chibios, 10)	12m 1s
build (stm32h7, chibios, 10)	10m 46s
build (fmuv2-plane, chibios, 10)	6m 1s
build (periph-build, chibios, 10)	8m 46s
build (iofirmware, chibios, 10)	3m 55s
build (CubeOrange-bootloader, chibios, 10)	3m 5s
build (fmuv3-bootloader, chibios, 10)	3m 5s
build (revo-bootloader, chibios, 10)	3m 17s
build (stm32h7-debug, chibios, 10)	9m 25s
build (fmuv3, chibios, 10)	13m 33s
build (revo-mini, chibios, 10)	11m 18s
build (MatekF405-Wing, chibios, 10)	11m 44s
build (CubeOrange-ODID, chibios, 10)	8m 20s
build (CubeRedPrimary-bootloader, chibios, 10)	3m 0s
build (configure-all, chibios, 10)	12m 28s
build (build-options-defaults-test, chibios, 10)	21m 3s
build (signing, chibios, 10)	8m 12s
build (CubeOrange-PPP, chibios, 10)	6m 48s
build (SOHW, chibios, 10)	11m 38s
build (Pixhawk6X-PPPGW, chibios, 10)	3m 53s
build (new-check, chibios, 10)	12m 33s
	3h 4m 51s

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