mtd: nane: print source of error message

Add the function name to the error message.

These messages are not very helpful:

[183356.176682] uncorrectable error :
[183356.180273] uncorrectable error :
[183356.184194] uncorrectable error :
[183356.187773] uncorrectable error :
[183356.191280] uncorrectable error :

Artem: amended the patch a bit
Signed-off-by: Tormod Volden <debian.tormod@gmail.com>

drivers/mtd/nand/nand_ecc.c

@@ -55,8 +55,7 @@ struct mtd_info;
 #define MODULE_AUTHOR(x)	/* x */
 #define MODULE_DESCRIPTION(x)	/* x */
 
-#define printk printf
-#define KERN_ERR		""
+#define pr_err printf
 #endif
 
 /*
@@ -507,7 +506,7 @@ int __nand_correct_data(unsigned char *buf,
 	if ((bitsperbyte[b0] + bitsperbyte[b1] + bitsperbyte[b2]) == 1)
 		return 1;	/* error in ECC data; no action needed */
 
-	printk(KERN_ERR "uncorrectable error : ");
+	pr_err("%s: uncorrectable ECC error", __func__);
 	return -1;
 }
 EXPORT_SYMBOL(__nand_correct_data);