NUCLEOF103RG target

NUCLEOF103RG is a target for Nucleo-F103RG (Nucleo-F103RB transplanted
with STM32F103RG which has 1MB of FLASH).
Such hardware with this target comes in handy when a firmware that
doesn't fit in smaller FLASH variant when compiled with DEBUG option.

The target definition files are straight copy of NAZE, except LED0_PIN
has been redefined to use Nucleo's LD2 (User LED).

It is also easy to convert exisiting F1 targets to be built to run on
the Nucleo-F103RG board:

- Add
    #define FLASH_PAGE_SIZE 0x800
    to target.h

- Also add
    #undef USE_DSHOT
    #undef USE_LED_STRIP
    #undef USE_TRANSPONDER
    #undef USE_CAMERA_CONTROL
    to target.h to avoid non-F1 compatible code from getting in.

- Add
FLASH_SIZE  = 1024
    to target.mk

src/link/stm32_flash_f103_1024k.ld

@@ -0,0 +1,25 @@
+/*
+*****************************************************************************
+**
+**  File        : stm32_flash_1m.ld
+**
+**  Abstract    : Linker script for STM32F103RG Device with
+**                1MByte FLASH, 96KByte RAM
+**
+*****************************************************************************
+*/
+
+/* Specify the memory areas. */
+MEMORY
+{
+    FLASH (rx)        : ORIGIN = 0x08000000, LENGTH = 1020K
+    FLASH_CONFIG (r)  : ORIGIN = 0x0803F000, LENGTH = 4K
+
+    RAM (xrw)         : ORIGIN = 0x20000000, LENGTH = 96K
+    MEMORY_B1 (rx)    : ORIGIN = 0x60000000, LENGTH = 0K
+}
+
+REGION_ALIAS("STACKRAM", RAM)
+REGION_ALIAS("FASTRAM", RAM)
+
+INCLUDE "stm32_flash.ld"