Add LOWPOWERTIMER for NUCLEO_F401RE and DISCO_F429ZI

Author: jeromecoutant

targets/targets.json

@@ -816,7 +816,7 @@
         "inherits": ["Target"],
         "detect_code": ["0720"],
         "macros": ["TRANSACTION_QUEUE_SIZE_SPI=2", "USB_STM_HAL", "USBHOST_OTHER"],
-        "device_has": ["ANALOGIN", "ERROR_RED", "I2C", "I2CSLAVE", "I2C_ASYNCH", "INTERRUPTIN", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "RTC", "SERIAL", "SERIAL_ASYNCH", "SERIAL_FC", "SLEEP", "SPI", "SPISLAVE", "SPI_ASYNCH", "STDIO_MESSAGES"],
+        "device_has": ["LOWPOWERTIMER", "ANALOGIN", "ERROR_RED", "I2C", "I2CSLAVE", "I2C_ASYNCH", "INTERRUPTIN", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "RTC", "SERIAL", "SERIAL_ASYNCH", "SERIAL_FC", "SLEEP", "SPI", "SPISLAVE", "SPI_ASYNCH", "STDIO_MESSAGES"],
         "release_versions": ["2", "5"],
         "device_name": "STM32F401RE"
     },
@@ -1169,7 +1169,7 @@
         "extra_labels": ["STM", "STM32F4", "STM32F429", "STM32F429ZI", "STM32F429xx"],
         "macros": ["RTC_LSI=1","TRANSACTION_QUEUE_SIZE_SPI=2", "USBHOST_OTHER"],
         "supported_toolchains": ["ARM", "uARM", "GCC_ARM", "IAR"],
-        "device_has": ["ANALOGIN", "ANALOGOUT", "CAN", "ERROR_RED", "I2C", "I2CSLAVE", "I2C_ASYNCH", "INTERRUPTIN", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "RTC", "SERIAL", "SERIAL_ASYNCH", "SERIAL_FC", "SLEEP", "SPI", "SPISLAVE", "SPI_ASYNCH", "STDIO_MESSAGES", "TRNG"],
+        "device_has": ["LOWPOWERTIMER", "ANALOGIN", "ANALOGOUT", "CAN", "ERROR_RED", "I2C", "I2CSLAVE", "I2C_ASYNCH", "INTERRUPTIN", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "RTC", "SERIAL", "SERIAL_ASYNCH", "SERIAL_FC", "SLEEP", "SPI", "SPISLAVE", "SPI_ASYNCH", "STDIO_MESSAGES", "TRNG"],
         "release_versions": ["2", "5"],
         "device_name": "STM32F429ZI"
     },