target_Gigadevice: Set the heap size and limit

Author: Deepika

targets/TARGET_GigaDevice/TARGET_GD32F30X/TARGET_GD32F307VG/device/TOOLCHAIN_GCC_ARM/GD32F307xG.ld

@@ -110,6 +110,7 @@ SECTIONS
         __end__ = .;
         end = __end__;
         *(.heap*)
+        . = ORIGIN(RAM) + LENGTH(RAM) - STACK_SIZE;
         __HeapLimit = .;
     } > RAM
 

targets/TARGET_GigaDevice/mbed_rtx.h

@@ -45,15 +45,4 @@
 
 #endif
 
-#if (defined(__GNUC__) && !defined(__CC_ARM) && !defined(__ARMCC_VERSION) && defined(TWO_RAM_REGIONS))
-extern uint32_t               __StackLimit[];
-extern uint32_t               __StackTop[];
-extern uint32_t               __end__[];
-extern uint32_t               __HeapLimit[];
-#define HEAP_START            ((unsigned char*)__end__)
-#define HEAP_SIZE             ((uint32_t)((uint32_t)__HeapLimit - (uint32_t)HEAP_START))
-#define ISR_STACK_START       ((unsigned char*)__StackLimit)
-#define ISR_STACK_SIZE        ((uint32_t)((uint32_t)__StackTop - (uint32_t)__StackLimit))
-#endif
-
 #endif  /* MBED_MBED_RTX_H */