Allow root to choose vfat policy to UTF8

Hi,

Right now the kernel detects the sysadmin trying to set the iocharset of vfat to UTF8 and prevents this with an error. While I can see that this is not recommended, enforcing this is policy that probably doesn't belong in the kernel. The patch below makes this situation a warning and a recommendation instead of a strong blockage.

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=126641

is an example of a sysadmin disliking this policy enforcement.

Greetings,
Arjan van de Ven

@@ -499,9 +499,8 @@
 	}
 	/* UTF8 doesn't provide FAT semantics */
 	if (!strcmp(opts->iocharset, "utf8")) {
-		printk(KERN_ERR "FAT: utf8 is not a valid IO charset"
-		       " for FAT filesystems\n");
-		return -EINVAL;
+		printk(KERN_ERR "FAT: utf8 is not a recommended IO charset"
+		       " for FAT filesystems, filesystem will be case sensitive!\n");
 	}
 
 	if (opts->unicode_xlate)