fbcon: Set rotate_font callback with related callbacks

The field struct fbcon_par.rotate_font points to fbcon_rotate_font() if
the console is rotated. Set the callback in the same place as the other
callbacks. Prepares for declaring all fbcon callbacks in a dedicated
struct type.

If not rotated, fbcon_set_bitops() still clears the callback to NULL.

Signed-off-by: Thomas Zimmermann <[e-mail]>
Reviewed-by: Sam Ravnborg <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/video/fbdev/core/fbcon_ccw.c

···
 	par->clear_margins = ccw_clear_margins;
 	par->cursor = ccw_cursor;
 	par->update_start = ccw_update_start;
+	par->rotate_font = fbcon_rotate_font;
 }

drivers/video/fbdev/core/fbcon_cw.c

···
 	par->clear_margins = cw_clear_margins;
 	par->cursor = cw_cursor;
 	par->update_start = cw_update_start;
+	par->rotate_font = fbcon_rotate_font;
 }

drivers/video/fbdev/core/fbcon_rotate.c

···
 #include "fbcon.h"
 #include "fbcon_rotate.h"
 
-static int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
+int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 {
 	struct fbcon_par *par = info->fbcon_par;
 	int len, err = 0;
···
 
 void fbcon_set_rotate(struct fbcon_par *par)
 {
-	par->rotate_font = fbcon_rotate_font;
-
 	switch (par->rotate) {
 	case FB_ROTATE_CW:
 		fbcon_rotate_cw(par);

drivers/video/fbdev/core/fbcon_rotate.h

···
 	}
 }
 
+int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc);
+
 extern void fbcon_rotate_cw(struct fbcon_par *par);
 extern void fbcon_rotate_ud(struct fbcon_par *par);
 extern void fbcon_rotate_ccw(struct fbcon_par *par);
+
 #endif

drivers/video/fbdev/core/fbcon_ud.c

···
 	par->clear_margins = ud_clear_margins;
 	par->cursor = ud_cursor;
 	par->update_start = ud_update_start;
+	par->rotate_font = fbcon_rotate_font;
 }