memory.x: RM CONFIG MEMORY area in linker script

- STM32f407 does not have second bank or flash/ Sector 12 unlike F427

memory.x

@@ -3,8 +3,6 @@
 MEMORY
 {
   FLASH (rx)      : ORIGIN = 0x8000000, LENGTH = 1024K
-  /* reserved for config data */
-  CONFIG (rx)     : ORIGIN = 0x8100000, LENGTH = 16K
   RAM (xrw)       : ORIGIN = 0x20000000, LENGTH = 112K - 4
   /* reserved for DFU trigger message */
   DFU_MSG (wrx)   : ORIGIN = 0x2001BFFC, LENGTH = 4
@@ -14,6 +12,5 @@ MEMORY
 }
 
 _flash_start = ORIGIN(FLASH);
-_config_start = ORIGIN(CONFIG);
 _dfu_msg = ORIGIN(DFU_MSG);
 _stack_start = ORIGIN(CCMRAM) + LENGTH(CCMRAM);