hwdef: added MatekL431-GPS build

this sets up for DMA on GPS UARTs, disables unnecessary UARTs and SPI
and disables unnecessary sensor types

the changes make moving baseline GPS with two DroneCAN GPS modules on
MatekL431 much more reliable

libraries/AP_HAL_ChibiOS/hwdef/MatekL431-GPS/hwdef-bl.dat

@@ -0,0 +1,3 @@
+include ../MatekL431/hwdef-bl.inc
+
+define CAN_APP_NODE_NAME "org.ardupilot.MatekL431-GPS"

libraries/AP_HAL_ChibiOS/hwdef/MatekL431-GPS/hwdef.dat

@@ -0,0 +1,55 @@
+include ../MatekL431/hwdef.inc
+
+define CAN_APP_NODE_NAME "org.ardupilot.MatekL431-GPS"
+
+# enable GPS and compass
+define HAL_PERIPH_ENABLE_GPS
+define GPS_MAX_RATE_MS 200
+
+define GPS_MAX_RECEIVERS 1
+define GPS_MAX_INSTANCES 1
+
+define HAL_PERIPH_GPS_PORT_DEFAULT 2
+
+# allow for F9P GPS modules with moving baseline
+define GPS_MOVING_BASELINE 1
+
+define HAL_PERIPH_ENABLE_MAG
+
+define HAL_COMPASS_MAX_SENSORS 1
+
+SPIDEV  rm3100 SPI1 DEVID1   MAG_CS MODE0  1*MHZ  1*MHZ
+COMPASS RM3100 SPI:rm3100 false ROTATION_PITCH_180
+
+# QMC5883L for different board varients
+COMPASS QMC5883L I2C:0:0xd false ROTATION_PITCH_180_YAW_90
+
+# disable USART1
+undef PB6
+undef PB7
+
+# disable USART2
+undef PA2
+undef PA3
+
+# enable GPS port with DMA
+undef PB10
+undef PB11
+PB10  USART3_TX USART3 SPEED_HIGH
+PB11  USART3_RX USART3 SPEED_HIGH
+
+# no ADC pins
+define HAL_USE_ADC FALSE
+
+# disable unnecessary threads
+define HAL_NO_MONITOR_THREAD
+define HAL_NO_RCIN_THREAD
+define HAL_NO_RCOUT_THREAD
+define HAL_NO_TIMER_THREAD
+
+# maintain GPS port number compatibility with MatekL431-Periph
+SERIAL_ORDER EMPTY EMPTY USART3
+
+# larger CAN pool for RTCM data
+undef HAL_CAN_POOL_SIZE
+define HAL_CAN_POOL_SIZE 12000