Update stm32f429 linker scripts for bootloader

Add MBED_APP_START and MBED_APP_SIZE to the stm32f429's linker script
so the start and size of an image can be specified. This allows the
ROM to be split into a bootloader region and an application region.

Author: c1728p9

targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F429xI/device/TOOLCHAIN_ARM_MICRO/stm32f429xx.sct

@@ -1,3 +1,4 @@
+#! armcc -E
 ; Scatter-Loading Description File
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ; Copyright (c) 2015, STMicroelectronics
@@ -27,10 +28,18 @@
 ; OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+#if !defined(MBED_APP_START)
+  #define MBED_APP_START 0x08000000
+#endif
+
+#if !defined(MBED_APP_SIZE)
+  #define MBED_APP_SIZE 0x200000
+#endif
+
 ; 2 MB FLASH (0x200000) + 256 KB SRAM (0x40000)
-LR_IROM1 0x08000000 0x200000  {    ; load region size_region
+LR_IROM1 MBED_APP_START MBED_APP_SIZE  {    ; load region size_region
 
-  ER_IROM1 0x08000000 0x200000  {  ; load address = execution address
+  ER_IROM1 MBED_APP_START MBED_APP_SIZE  {  ; load address = execution address
    *.o (RESET, +First)
    *(InRoot$$Sections)
    .ANY (+RO)

targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F429xI/device/TOOLCHAIN_ARM_STD/stm32f429xx.sct

@@ -1,3 +1,4 @@
+#! armcc -E
 ; Scatter-Loading Description File
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ; Copyright (c) 2015, STMicroelectronics
@@ -27,10 +28,18 @@
 ; OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+#if !defined(MBED_APP_START)
+  #define MBED_APP_START 0x08000000
+#endif
+
+#if !defined(MBED_APP_SIZE)
+  #define MBED_APP_SIZE 0x200000
+#endif
+
 ; 2 MB FLASH (0x200000) + 192 KB SRAM (0x30000)
-LR_IROM1 0x08000000 0x200000  {    ; load region size_region
+LR_IROM1 MBED_APP_START MBED_APP_SIZE  {    ; load region size_region
 
-  ER_IROM1 0x08000000 0x200000  {  ; load address = execution address
+  ER_IROM1 MBED_APP_START MBED_APP_SIZE  {  ; load address = execution address
    *.o (RESET, +First)
    *(InRoot$$Sections)
    .ANY (+RO)

targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F429xI/device/TOOLCHAIN_GCC_ARM/STM32F429xI.ld

@@ -10,11 +10,19 @@ STACK_SIZE = 0x400;
  * heap and the page heap in uVisor applications. */
 HEAP_SIZE = 0x6000;
 
+#if !defined(MBED_APP_START)
+  #define MBED_APP_START 0x08000000
+#endif
+
+#if !defined(MBED_APP_SIZE)
+  #define MBED_APP_SIZE 2048k
+#endif
+
 /* Specify the memory areas */
 MEMORY
 {
-    VECTORS (rx) : ORIGIN = 0x08000000, LENGTH = 0x400
-    FLASH (rx)   : ORIGIN = 0x08000400, LENGTH = 2048k - 0x400
+    VECTORS (rx) : ORIGIN = MBED_APP_START, LENGTH = 0x400
+    FLASH (rx)   : ORIGIN = MBED_APP_START + 0x400, LENGTH = MBED_APP_SIZE - 0x400
     CCM (rwx)    : ORIGIN = 0x10000000, LENGTH = 64K
     RAM (rwx)    : ORIGIN = 0x20000000, LENGTH = 192k
 }

targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F429xI/device/TOOLCHAIN_IAR/stm32f429xx_flash.icf

@@ -1,11 +1,13 @@
 /*###ICF### Section handled by ICF editor, don't touch! ****/
 /*-Editor annotation file-*/
 /* IcfEditorFile="$TOOLKIT_DIR$\config\ide\IcfEditor\cortex_v1_0.xml" */
+if (!isdefinedsymbol(MBED_APP_START)) { define symbol MBED_APP_START = 0x08000000; }
+if (!isdefinedsymbol(MBED_APP_SIZE)) { define symbol MBED_APP_SIZE = 0x200000; }
 /*-Specials-*/
-define symbol __ICFEDIT_intvec_start__ = 0x08000000;
+define symbol __ICFEDIT_intvec_start__ = MBED_APP_START;
 /*-Memory Regions-*/
-define symbol __ICFEDIT_region_ROM_start__    = 0x08000000;
-define symbol __ICFEDIT_region_ROM_end__      = 0x081FFFFF;
+define symbol __ICFEDIT_region_ROM_start__    = MBED_APP_START;
+define symbol __ICFEDIT_region_ROM_end__      = MBED_APP_START + MBED_APP_SIZE - 1;
 define symbol __ICFEDIT_region_NVIC_start__   = 0x20000000;
 define symbol __ICFEDIT_region_NVIC_end__     = 0x200001AF;
 define symbol __ICFEDIT_region_RAM_start__    = 0x200001B0;