AP_ExternalAHRS: Populate Microstrain7 orientation from filter #36120

Job	Run time
build (stm32f7, chibios, 10)	4m 1s
build (stm32h7, chibios, 10)	3m 26s
build (fmuv2-plane, chibios, 10)	2m 7s
build (periph-build, chibios, 10)	3m 45s
build (iofirmware, chibios, 10)	1m 39s
build (CubeOrange-bootloader, chibios, 10)	1m 7s
build (fmuv3-bootloader, chibios, 10)	1m 3s
build (revo-bootloader, chibios, 10)	50s
build (stm32h7-debug, chibios, 10)	2m 43s
build (fmuv3, chibios, 10)	5m 25s
build (revo-mini, chibios, 10)	4m 0s
build (MatekF405-Wing, chibios, 10)	4m 19s
build (CubeOrange-ODID, chibios, 10)	2m 31s
build (CubeRedPrimary-bootloader, chibios, 10)	55s
build (configure-all, chibios, 10)	9m 14s
build (build-options-defaults-test, chibios, 10)	6m 2s
build (signing, chibios, 10)	3m 7s
build (CubeOrange-PPP, chibios, 10)	2m 9s
build (CubeOrange-SOHW, chibios, 10)	2m 4s
build (Pixhawk6X-PPPGW, chibios, 10)	1m 12s
	1h 1m 39s

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