Convert CONFIG_STANDALONE_LOAD_ADDR to Kconfig

This converts the following to Kconfig:
   CONFIG_STANDALONE_LOAD_ADDR

Signed-off-by: Tom Rini <trini@konsulko.com>

api/Kconfig

@@ -11,3 +11,22 @@ config SYS_MMC_MAX_DEVICE
 	default 1
 
 endmenu
+
+config STANDALONE_LOAD_ADDR
+	hex "Address in memory to link standalone applications to"
+	default 0xffffffff80200000 if MIPS && 64BIT
+	default 0x8c000000 if SH
+	default 0x82000000 if ARC
+	default 0x80f00000 if MICROBLAZE
+	default 0x80300000 if ARCH_OMAP2PLUS || FSL_LSCH2 || FSL_LSCH3
+	default 0x80200000 if MIPS && 32BIT
+	default 0x0c100000 if ARM
+	default 0x02000000 if NIOS2
+	default 0x00040000 if PPC || X86
+	default 0x00020000 if M68K
+	default 0x0 if RISCV
+	default SYS_LOAD_ADDR
+	help
+	  This option defines a board specific value for the address where
+	  standalone program gets loaded, thus overwriting the architecture
+	  dependent default settings.