auxdisplay: hd44780: Convert to use charlcd_free()

Convert to use charlcd_free() instead of kfree() for sake of type check.

Reviewed-by: Geert Uytterhoeven <[e-mail]>
Signed-off-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Miguel Ojeda <[e-mail]>

drivers/auxdisplay/hd44780.c

···
 	return 0;
 
 fail:
-	kfree(lcd);
+	charlcd_free(lcd);
 	return ret;
 }
 
···
 
 	charlcd_unregister(lcd);
 
-	kfree(lcd);
+	charlcd_free(lcd);
 	return 0;
 }