RM138: Add initial support for STM32F4 SOM kernel

v4.x to s/w load&test procedure.
Needed to set MAX_ARGS to a larger value in U-boot for the upgrade macros

include/configs/stm-som.h

@@ -397,7 +397,7 @@
 /*
  * Max number of command args
  */
-#define CONFIG_SYS_MAXARGS		16
+#define CONFIG_SYS_MAXARGS		48
 
 /*
  * Auto-boot sequence configuration