ARM: zynq: Use memory initialization based on DTS file

Remove hardcoded memory sizes. Use information from DT memory node.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>

include/configs/zynq-common.h

@@ -278,14 +278,14 @@
 #define CONFIG_SYS_TEXT_BASE		0x4000000
 
 #define CONFIG_NR_DRAM_BANKS		1
-#define CONFIG_SYS_SDRAM_BASE		0
 
-#define CONFIG_SYS_MEMTEST_START	CONFIG_SYS_SDRAM_BASE
-#define CONFIG_SYS_MEMTEST_END		(CONFIG_SYS_SDRAM_BASE + 0x1000)
+#define CONFIG_SYS_MEMTEST_START	0
+#define CONFIG_SYS_MEMTEST_END		0x1000
 
 #define CONFIG_SYS_MALLOC_LEN		0x1400000
-#define CONFIG_SYS_INIT_RAM_ADDR	CONFIG_SYS_SDRAM_BASE
-#define CONFIG_SYS_INIT_RAM_SIZE	CONFIG_SYS_MALLOC_LEN
+
+#define CONFIG_SYS_INIT_RAM_ADDR	0xFFFF0000
+#define CONFIG_SYS_INIT_RAM_SIZE	0x1000
 #define CONFIG_SYS_INIT_SP_ADDR		(CONFIG_SYS_INIT_RAM_ADDR + \
 					CONFIG_SYS_INIT_RAM_SIZE - \
 					GENERATED_GBL_DATA_SIZE)