Plane: add missing AccZ bit from GCS_PID_MASK doc #37

Job	Run time
build (stm32f7, chibios, 10)	13m 22s
build (stm32h7, chibios, 10)	13m 4s
build (fmuv2-plane, chibios, 10)	6m 3s
build (periph-build, chibios, 10)	12m 10s
build (iofirmware, chibios, 10)	2m 15s
build (CubeOrange-bootloader, chibios, 10)	1m 31s
build (fmuv3-bootloader, chibios, 10)	1m 3s
build (revo-bootloader, chibios, 10)	1m 29s
build (stm32h7-debug, chibios, 10)	6m 54s
build (fmuv3, chibios, 10)	13m 51s
build (revo-mini, chibios, 10)	10m 36s
build (MatekF405-Wing, chibios, 10)	10m 56s
build (CubeOrange-ODID, chibios, 10)	8m 1s
build (CubeRedPrimary-bootloader, chibios, 10)	1m 8s
build (configure-all, chibios, 10)	11m 27s
build (build-options-defaults-test, chibios, 10)	23m 48s
build (signing, chibios, 10)	9m 2s
build (CubeOrange-PPP, chibios, 10)	6m 56s
build (CubeRed-EKF2, chibios, 10)	6m 32s
build (SOHW, chibios, 10)	10m 36s
build (Pixhawk6X-PPPGW, chibios, 10)	2m 52s
build (new-check, chibios, 10)	13m 38s
	3h 7m 14s

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