configfs: Correct error value returned by API config_item_set_name()

kvasprintf() failure is often caused by memory allocation which has error
code -ENOMEM, but config_item_set_name() returns -EFAULT for the failure.

Fix by returning -ENOMEM instead of -EFAULT for the failure.

Reviewed-by: Joel Becker <[e-mail]>
Reviewed-by: Breno Leitao <[e-mail]>
Signed-off-by: Zijun Hu <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Andreas Hindborg <[e-mail]>

fs/configfs/item.c

···
 		name = kvasprintf(GFP_KERNEL, fmt, args);
 		va_end(args);
 		if (!name)
-			return -EFAULT;
+			return -ENOMEM;
 	}
 
 	/* Free the old name, if necessary. */