nxp: ls102xa: add LS1 PSCI system suspend

The deep sleep function of LS1 platform, is mapped into PSCI system
suspend function, this patch adds implementation of it.

Signed-off-by: Hongbo Zhang <hongbo.zhang@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/arch/arm/cpu/armv7/ls102xa/Makefile b/arch/arm/cpu/armv7/ls102xa/Makefile
index 0228300..f8300c7 100644
--- a/arch/arm/cpu/armv7/ls102xa/Makefile
+++ b/arch/arm/cpu/armv7/ls102xa/Makefile
@@ -16,5 +16,5 @@
 obj-$(CONFIG_SPL) += spl.o
 
 ifdef CONFIG_ARMV7_PSCI
-obj-y  += psci.o
+obj-y  += psci.o ls102xa_psci.o
 endif