ARM: socfpga: Increase Malloc pool size to support FAT filesystem in SPL

Increasing Malloc pool size up to 0x15000 is required to support FAT in SPL
. The result of calculation is come from default max cluster(0x10000) +
others(0x2000) + additional memory for headroom(0x3000).
Signed-off-by: NTien Fong Chee <tien.fong.chee@intel.com>

include/configs/socfpga_arria10_socdk.h

 /* SPDX-License-Identifier: GPL-2.0 */
 /*
- *  Copyright (C) 2015-2017 Altera Corporation <www.altera.com>
+ *  Copyright (C) 2015-2019 Altera Corporation <www.altera.com>
  */
 
 #ifndef __CONFIG_SOCFGPA_ARRIA10_H__
@@ -36,6 +36,9 @@
  */
 #define CONFIG_SYS_MAX_FLASH_BANKS     1
 
+/* SPL memory allocation configuration, this is for FAT implementation */
+#define CONFIG_SYS_SPL_MALLOC_SIZE	0x00015000
+
 /* The rest of the configuration is shared */
 #include <configs/socfpga_common.h>