arm: SC594-SOM-EZKIT initial support

Adds support for Analog Devices' SC594-SOM-EZKIT board. Includes:
- SoC specific configs in mach-sc5xx/Kconfig
- Memory Map for SPL
- SPL config options in common/spl/Kconfig
- 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: Trevor Woerner <twoerner@gmail.com>
Signed-off-by: Trevor Woerner <twoerner@gmail.com>
Co-developed-by: Nathan Barrett-Morrison <nathan.morrison@timesys.com>
Signed-off-by: Nathan Barrett-Morrison <nathan.morrison@timesys.com>
Co-developed-by: Ian Roberts <ian.roberts@timesys.com>
Signed-off-by: Ian Roberts <ian.roberts@timesys.com>
Signed-off-by: Oliver Gaskell <Oliver.Gaskell@analog.com>
diff --git a/Kconfig b/Kconfig
index 1596139..f797105 100644
--- a/Kconfig
+++ b/Kconfig
@@ -646,6 +646,7 @@
 	default 0x4a000000 if SUNXI_MINIMUM_DRAM_MB >= 256
 	default 0x42e00000 if SUNXI_MINIMUM_DRAM_MB >= 64
 	default 0x96000000 if ARCH_SC5XX && SC59X_64
+	default 0xB2200000 if ARCH_SC5XX && SC59X
 	hex "Text Base"
 	help
 	  The address in memory that U-Boot will be copied and executed from