Revert "sunxi: Move the SPL stack top to 0x1A000 on Allwinner A64/A80"

This commit moved the SPL stack into SRAM C, which worked when the SPL
set the AHB1 clock down to 100 MHz to cope with the flaky SRAM C access
from the CPU.
However booting with boot0 (and thus not using SPL at all) we still run
with a 200 MHz AHB1, so any access to SRAM C is prone to fail.
Since this commit does _not_ only affect the SPL code, but also the
U-Boot proper, we fail when booting with boot0.

As the introduction of tiny-printf reduced the size of the SPL, we
can afford to have the SPL stack in SRAM A1.

This reverts commit 1a83fb4a
and fixes booting the Pine64 when using boot0.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Reviewed-by: NSiarhei Siamashka <siarhei.siamashka@gmail.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>

include/configs/sunxi-common.h

@@ -99,7 +99,7 @@
  * the 1 actually activates the mapping of the first 32 KiB to 0x00000000.
  */
 #define CONFIG_SYS_INIT_RAM_ADDR	0x10000
-#define CONFIG_SYS_INIT_RAM_SIZE	0xA000	/* 40 KiB */
+#define CONFIG_SYS_INIT_RAM_SIZE	0x08000	/* FIXME: 40 KiB ? */
 #else
 #define CONFIG_SYS_INIT_RAM_ADDR	0x0
 #define CONFIG_SYS_INIT_RAM_SIZE	0x8000	/* 32 KiB */
@@ -220,7 +220,8 @@
 #define CONFIG_SPL_PAD_TO		32768		/* decimal for 'dd' */
 
 #if defined(CONFIG_MACH_SUN9I) || defined(CONFIG_MACH_SUN50I)
-#define LOW_LEVEL_SRAM_STACK		0x0001A000
+/* FIXME: 40 KiB instead of 32 KiB ? */
+#define LOW_LEVEL_SRAM_STACK		0x00018000
 #define CONFIG_SPL_STACK		LOW_LEVEL_SRAM_STACK
 #else
 /* end of 32 KiB in sram */