MIPS: add Kconfig option for CONFIG_SWAP_IO_SPACE

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index d87cbb4..ef78929 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -29,6 +29,7 @@
 	select SUPPORTS_LITTLE_ENDIAN
 	select SUPPORTS_CPU_MIPS32_R1
 	select SUPPORTS_CPU_MIPS32_R2
+	select SWAP_IO_SPACE
 
 config TARGET_VCT
 	bool "Support vct"
@@ -181,6 +182,9 @@
 config 64BIT
 	bool
 
+config SWAP_IO_SPACE
+	bool
+
 endif
 
 endmenu