Put device_name in upper-case in targets.json

Author: bcostm

targets/targets.json

@@ -1332,7 +1332,7 @@
         "macros": ["TRANSACTION_QUEUE_SIZE_SPI=2", "USBHOST_OTHER"],
         "device_has": ["ANALOGIN", "ANALOGOUT", "CAN", "I2C", "I2CSLAVE", "I2C_ASYNCH", "INTERRUPTIN", "LOWPOWERTIMER", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "RTC", "SERIAL", "SERIAL_FC", "SLEEP", "SPI", "SPISLAVE", "SPI_ASYNCH", "STDIO_MESSAGES", "TRNG"],
         "release_versions": ["2", "5"],
-        "device_name": "stm32l475vg"
+        "device_name": "STM32L475VG"
     },
     "DISCO_L476VG": {
         "inherits": ["Target"],