AP_GPS: Expose COM port and Output Rate in header, Fix default COM port #33015

Job	Run time
build (stm32f7, chibios, 10)	20m 49s
build (stm32h7, chibios, 10)	21m 48s
build (fmuv2-plane, chibios, 10)	8m 4s
build (periph-build, chibios, 10)	36m 58s
build (iofirmware, chibios, 10)	2m 35s
build (CubeOrange-bootloader, chibios, 10)	1m 28s
build (fmuv3-bootloader, chibios, 10)	1m 30s
build (revo-bootloader, chibios, 10)	1m 55s
build (stm32h7-debug, chibios, 10)	6m 34s
build (fmuv3, chibios, 10)	22m 24s
build (revo-mini, chibios, 10)	14m 54s
build (MatekF405-Wing, chibios, 10)	11m 17s
build (CubeOrange-ODID, chibios, 10)	8m 12s
build (CubeRedPrimary-bootloader, chibios, 10)	1m 41s
build (configure-all, chibios, 10)	8m 36s
build (build-options-defaults-test, chibios, 10)	34m 56s
build (signing, chibios, 10)	9m 6s
	3h 32m 47s

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