arm: SC573-EZKIT initial support

Adds support for Analog Devices' SC573-EZKIT board. Includes:
- SoC specific configs in mach-sc5xx/Kconfig
- Memory Map for SPL
- Necessary board-specific init functions
- Board-specific Kconfig and environment in board/adi/
- Memory configuration

Co-developed-by: Greg Malysa <greg.malysa@timesys.com>
Signed-off-by: Greg Malysa <greg.malysa@timesys.com>
Co-developed-by: Nathan Barrett-Morrison <nathan.morrison@timesys.com>
Signed-off-by: Nathan Barrett-Morrison <nathan.morrison@timesys.com>
Signed-off-by: Oliver Gaskell <Oliver.Gaskell@analog.com>
diff --git a/arch/arm/mach-sc5xx/Makefile b/arch/arm/mach-sc5xx/Makefile
index 9a00a43..cac768b 100644
--- a/arch/arm/mach-sc5xx/Makefile
+++ b/arch/arm/mach-sc5xx/Makefile
@@ -11,6 +11,7 @@
 obj-y += soc.o init/
 
 obj-$(CONFIG_SC57X) += sc57x.o
+obj-$(CONFIG_SC57X) += sc57x-spl.o
 obj-$(CONFIG_SC58X) += sc58x.o
 obj-$(CONFIG_SC58X) += sc58x-spl.o
 obj-$(CONFIG_SC59X) += sc59x.o