Make flash protection work, when the environment is in EEPROM

On the pcm030 the environment is located in the onboard EEPROM. But we want
to handle flash sector protection in a safe manner. So we must read the
unlock environment variable from EEPROM instead from flash.

This patch is required as long the evironment is saved into the EEPROM.

Stefan: Additional change as suggested by Wolfgang, use bigger char array
(instead of 4).
Signed-off-by: NEric Schumann <E.Schumann@phytec.de>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Acked-by: NWolfgang Denk <wd@denx.de>
Signed-off-by: NStefan Roese <sr@denx.de>

drivers/mtd/cfi_flash.c

@@ -2009,7 +2009,9 @@ unsigned long flash_init (void)
 #endif
 
 #ifdef CONFIG_SYS_FLASH_PROTECTION
-	char *s = getenv("unlock");
+	/* read environment from EEPROM */
+	char s[64];
+	getenv_r ("unlock", s, sizeof(s));
 #endif
 
 #define BANK_BASE(i)	(((phys_addr_t [CFI_MAX_FLASH_BANKS])CONFIG_SYS_FLASH_BANKS_LIST)[i])