[Blackfin] arch: Initial checkin of the memory protection support.

Enable it with CONFIG_MPU.

Signed-off-by: Bernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index ce521a9..6b96d7d 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -765,6 +765,15 @@
 	  Set the max memory pieces for the L1 SRAM allocation algorithm.
 	  Min value is 16. Max value is 1024.
 
+
+config MPU
+	bool "Enable the memory protection unit (EXPERIMENTAL)"
+	default n
+	help
+	  Use the processor's MPU to protect applications from accessing
+	  memory they do not own.  This comes at a performance penalty
+	  and is recommended only for debugging.
+
 comment "Asynchonous Memory Configuration"
 
 menu "EBIU_AMGCTL Global Control"