NUCLEO_L476RG: FLASH size of 1MB, not 2MB

MBED_APP_SIZE was erroneously defined to 2MB for this target,
while it's only 1MB.

Author: LMESTM

targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L476xG/device/TOOLCHAIN_ARM_MICRO/stm32l476xx.sct

@@ -33,7 +33,7 @@
 #endif
 
 #if !defined(MBED_APP_SIZE)
-  #define MBED_APP_SIZE 0x200000
+  #define MBED_APP_SIZE 0x100000
 #endif
 
 ; 1MB FLASH (0x100000) + 128KB SRAM (0x20000)

targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L476xG/device/TOOLCHAIN_ARM_STD/stm32l476xx.sct

@@ -33,7 +33,7 @@
 #endif
 
 #if !defined(MBED_APP_SIZE)
-  #define MBED_APP_SIZE 0x200000
+  #define MBED_APP_SIZE 0x100000
 #endif
 
 ; 1MB FLASH (0x100000) + 128KB SRAM (0x20000)

targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L476xG/device/TOOLCHAIN_GCC_ARM/STM32L476XX.ld

@@ -3,7 +3,7 @@
 #endif
 
 #if !defined(MBED_APP_SIZE)
-  #define MBED_APP_SIZE 2048k
+  #define MBED_APP_SIZE 1024k
 #endif
 
 /* Linker script to configure memory regions. */

targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L476xG/device/TOOLCHAIN_IAR/stm32l476xx.icf

@@ -1,5 +1,5 @@
 if (!isdefinedsymbol(MBED_APP_START)) { define symbol MBED_APP_START = 0x08000000; }
-if (!isdefinedsymbol(MBED_APP_SIZE)) { define symbol MBED_APP_SIZE = 0x200000; }
+if (!isdefinedsymbol(MBED_APP_SIZE)) { define symbol MBED_APP_SIZE = 0x100000; }
 
 /* [ROM = 1024kb = 0x100000] */
 define symbol __intvec_start__     = MBED_APP_START;