Kconfig: Convert CONFIG_SYS_SRAM_BASE to Kconfig

This converts ad-hoc CONFIG_SYS_SRAM_BASE to Kconfig.
Reviewed-by: NSimon Glass <sjg@chromium.org>
Signed-off-by: NOvidiu Panait <ovidiu.panait@windriver.com>

Kconfig

@@ -390,6 +390,11 @@ config SYS_HAS_SRAM
 	  SRAM base address is controlled by CONFIG_SYS_SRAM_BASE.
 	  SRAM size is controlled by CONFIG_SYS_SRAM_SIZE.
 
+config SYS_SRAM_BASE
+	hex
+	default 0x80000000 if TARGET_PIC32MZDASK
+	default 0x0
+
 endmenu		# General setup
 
 menu "Boot images"

include/configs/pic32mzdask.h

@@ -19,7 +19,6 @@
 /*----------------------------------------------------------------------
  * Memory Layout
  */
-#define CONFIG_SYS_SRAM_BASE		0x80000000
 #define CONFIG_SYS_SRAM_SIZE		0x00080000 /* 512K */
 
 /* Initial RAM for temporary stack, global data */

scripts/config_whitelist.txt

@@ -3715,7 +3715,6 @@ CONFIG_SYS_SPL_LEN
 CONFIG_SYS_SPL_MALLOC_SIZE
 CONFIG_SYS_SPL_MALLOC_START
 CONFIG_SYS_SPR
-CONFIG_SYS_SRAM_BASE
 CONFIG_SYS_SRAM_SIZE
 CONFIG_SYS_SRAM_START
 CONFIG_SYS_SRIO