xilinx: zynqmp: increase CONFIG_SYS_SPL_MALLOC_SIZE to 16MB

commit 03f1f78a ("spl: fit: Prefer a malloc()'d buffer for loading
images")' changed the way buffer allocation worked for SPL to a more
flexible method.

For xilinx zynqmp the 1MB buffer is not necessarily enough when dealing
with complex fit images (e.g. containing FPGA/TF-A/OP-TEE/U-Boot
proper), which can easily reach up to 10MB, so increase the default
CONFIG_SYS_SPL_MALLOC_SIZE size to 16MB to cover more advanced
scenarios.
Signed-off-by: NRicardo Salveti <ricardo@foundries.io>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>

include/configs/xilinx_zynqmp.h

@@ -261,7 +261,7 @@
 #endif
 
 #define CONFIG_SYS_SPL_MALLOC_START	0x20000000
-#define CONFIG_SYS_SPL_MALLOC_SIZE	0x100000
+#define CONFIG_SYS_SPL_MALLOC_SIZE	0x1000000
 
 #ifdef CONFIG_SPL_SYS_MALLOC_SIMPLE
 # error "Disable CONFIG_SPL_SYS_MALLOC_SIMPLE. Full malloc needs to be used"