auxdisplay: charlcd: Introduce charlcd_free() helper

The charlcd_free() is a counterpart to charlcd_alloc()
and should be called symmetrically on tear down.
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMiguel Ojeda <miguel.ojeda.sandonis@gmail.com>

drivers/auxdisplay/charlcd.c

@@ -818,6 +818,12 @@ struct charlcd *charlcd_alloc(unsigned int drvdata_size)
 }
 EXPORT_SYMBOL_GPL(charlcd_alloc);
 
+void charlcd_free(struct charlcd *lcd)
+{
+	kfree(charlcd_to_priv(lcd));
+}
+EXPORT_SYMBOL_GPL(charlcd_free);
+
 static int panel_notify_sys(struct notifier_block *this, unsigned long code,
 			    void *unused)
 {

include/misc/charlcd.h

@@ -35,6 +35,7 @@ struct charlcd_ops {
 };
 
 struct charlcd *charlcd_alloc(unsigned int drvdata_size);
+void charlcd_free(struct charlcd *lcd);
 
 int charlcd_register(struct charlcd *lcd);
 int charlcd_unregister(struct charlcd *lcd);