revert mavlink submodule to uci-overRID #63

Job	Run time
build (stm32f7, chibios, 10)	15m 31s
build (stm32h7, chibios, 10)	14m 16s
build (fmuv2-plane, chibios, 10)	7m 52s
build (periph-build, chibios, 10)	14m 50s
build (iofirmware, chibios, 10)	4m 45s
build (CubeOrange-bootloader, chibios, 10)	3m 21s
build (fmuv3-bootloader, chibios, 10)	3m 30s
build (revo-bootloader, chibios, 10)	3m 20s
build (stm32h7-debug, chibios, 10)	9m 25s
build (fmuv3, chibios, 10)	15m 50s
build (revo-mini, chibios, 10)	12m 19s
build (MatekF405-Wing, chibios, 10)	13m 3s
build (CubeOrange-ODID, chibios, 10)	10m 32s
build (CubeRedPrimary-bootloader, chibios, 10)	3m 32s
build (configure-all, chibios, 10)	12m 55s
build (build-options-defaults-test, chibios, 10)	26m 1s
build (signing, chibios, 10)	11m 26s
build (CubeOrange-PPP, chibios, 10)	9m 7s
build (CubeRed-EKF2, chibios, 10)	10m 16s
build (SOHW, chibios, 10)	14m 35s
build (Pixhawk6X-PPPGW, chibios, 10)	5m 5s
build (new-check, chibios, 10)	15m 22s
	3h 56m 53s

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