tty: vt: make vc_is_sel()'s vc const

It's only an aid to people reading the header and/or calling
vc_is_sel(). vc is only tested there, so having it const makes sense.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-9-jirislaby@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/vt/selection.c

@@ -88,7 +88,7 @@ void clear_selection(void)
 }
 EXPORT_SYMBOL_GPL(clear_selection);
 
-bool vc_is_sel(struct vc_data *vc)
+bool vc_is_sel(const struct vc_data *vc)
 {
 	return vc == vc_sel.cons;
 }

include/linux/selection.h

@@ -24,7 +24,7 @@ extern int sel_loadlut(u32 __user *lut);
 extern int mouse_reporting(void);
 extern void mouse_report(struct tty_struct * tty, int butt, int mrx, int mry);
 
-bool vc_is_sel(struct vc_data *vc);
+bool vc_is_sel(const struct vc_data *vc);
 
 extern int console_blanked;