spl: Rename SYS_SPL_ARGS_ADDR to SPL_PAYLOAD_ARGS_ADDR

Rename this so that SPL is first, as per U-Boot convention. Also add
PAYLOAD_ since this is where in memory the parameters for the payload
have been stored.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/ls1046ardb_qspi_spl_defconfig b/configs/ls1046ardb_qspi_spl_defconfig
index 78f1185..84bd1b1 100644
--- a/configs/ls1046ardb_qspi_spl_defconfig
+++ b/configs/ls1046ardb_qspi_spl_defconfig
@@ -61,7 +61,7 @@
 CONFIG_SPL_MPC8XXX_INIT_DDR=y
 CONFIG_SPL_NOR_SUPPORT=y
 CONFIG_SPL_OS_BOOT=y
-CONFIG_SYS_SPL_ARGS_ADDR=0x90000000
+CONFIG_SPL_PAYLOAD_ARGS_ADDR=0x90000000
 CONFIG_SYS_OS_BASE=0x40980000
 CONFIG_SPL_WATCHDOG=y
 CONFIG_SPL_TARGET="spl/u-boot-spl.pbl"