STM32L0xx : GCC_ARM remove zero bss, in startup.

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

targets/TARGET_STM/TARGET_STM32L0/TARGET_DISCO_L053C8/device/TOOLCHAIN_GCC_ARM/startup_stm32l053xx.S

@@ -55,10 +55,6 @@ 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
 
     .section  .text.Reset_Handler
   .weak  Reset_Handler
@@ -83,19 +79,6 @@ 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]
-  adds r2, r2, #4
-
-
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
 
 /* Call the clock system intitialization function.*/
   bl  SystemInit

targets/TARGET_STM/TARGET_STM32L0/TARGET_NUCLEO_L011K4/device/TOOLCHAIN_GCC_ARM/startup_stm32l011xx.s

@@ -55,10 +55,6 @@ 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
 
     .section  .text.Reset_Handler
   .weak  Reset_Handler
@@ -83,19 +79,6 @@ 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]
-  adds r2, r2, #4
-
-
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
 
 /* Call the clock system intitialization function.*/
   bl  SystemInit

targets/TARGET_STM/TARGET_STM32L0/TARGET_NUCLEO_L031K6/device/TOOLCHAIN_GCC_ARM/startup_stm32l031xx.S

@@ -55,10 +55,6 @@ 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
 
     .section  .text.Reset_Handler
   .weak  Reset_Handler
@@ -83,20 +79,7 @@ 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]
-  adds r2, r2, #4
-
-
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
-
 /* Call the clock system intitialization function.*/
   bl  SystemInit
 /* Call static constructors */

targets/TARGET_STM/TARGET_STM32L0/TARGET_NUCLEO_L053R8/device/TOOLCHAIN_GCC_ARM/startup_stm32l053xx.S

@@ -55,10 +55,6 @@ 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
 
     .section  .text.Reset_Handler
   .weak  Reset_Handler
@@ -83,20 +79,7 @@ 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]
-  adds r2, r2, #4
-
-
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
-
 /* Call the clock system intitialization function.*/
   bl  SystemInit
 /* Call static constructors */

targets/TARGET_STM/TARGET_STM32L0/TARGET_NUCLEO_L073RZ/device/TOOLCHAIN_GCC_ARM/startup_stm32l073xx.S

@@ -55,10 +55,6 @@ 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
 
     .section  .text.Reset_Handler
   .weak  Reset_Handler
@@ -83,19 +79,6 @@ 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]
-  adds r2, r2, #4
-
-
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
 
 /* Call the clock system intitialization function.*/
   bl  SystemInit