STM32F207: GCC_ARM remove zero bss, in startup.

zero bss is done in libc init after call to _start.

Author: jamike

targets/TARGET_STM/TARGET_STM32F2/TARGET_NUCLEO_F207ZG/device/TOOLCHAIN_GCC_ARM/startup_stm32f207xx.s

@@ -57,10 +57,6 @@ defined in linker script */
 .word  _sdata
 /* end address for the .data section. defined in linker script */
 .word  _edata
-/* start address for the .bss section. defined in linker script */
-.word  _sbss
-/* end address for the .bss section. defined in linker script */
-.word  _ebss
 /* stack used for SystemInit_ExtMemCtl; always internal RAM used */
 
 /**
@@ -94,17 +90,6 @@ LoopCopyDataInit:
   adds  r2, r0, r1
   cmp  r2, r3
   bcc  CopyDataInit
-  ldr  r2, =_sbss
-  b  LoopFillZerobss
-/* Zero fill the bss segment. */
-FillZerobss:
-  movs  r3, #0
-  str  r3, [r2], #4
-
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
 
 /* Call the clock system initialization function.*/
   bl  SystemInit
@@ -520,4 +505,4 @@ g_pfnVectors:
    .weak      HASH_RNG_IRQHandler
    .thumb_set HASH_RNG_IRQHandler,Default_Handler
 
-/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
+/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/