mtd, cfi: introduce void flash_protect_default(void)

collect code which protects default sectors in a function, called
flash_protect_default. So boardspecific code can call it too.

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/include/flash.h b/include/flash.h
index 1b6821a..0ca70d9 100644
--- a/include/flash.h
+++ b/include/flash.h
@@ -92,6 +92,7 @@
 /* Prototypes */
 
 extern unsigned long flash_init (void);
+extern void flash_protect_default(void);
 extern void flash_print_info (flash_info_t *);
 extern int flash_erase	(flash_info_t *, int, int);
 extern int flash_sect_erase (ulong addr_first, ulong addr_last);