video: fbdev: mx3fb: Fix kernel-doc, set but not used and string warnings

Fix W=1 warnings:
- Fix kernel-doc
- Drop unused code/variables
- Use memcpy to copy a string without zero-termination
strncpy() generates a warning

v2:
- Updated subject (Lee)

Signed-off-by: Sam Ravnborg <[e-mail]>
Acked-by: Thomas Zimmermann <[e-mail]>
Cc: Sam Ravnborg <[e-mail]>
Cc: Jani Nikula <[e-mail]>
Cc: Laurent Pinchart <[e-mail]>
Cc: Daniel Vetter <[e-mail]>
Cc: Xiaofei Tan <[e-mail]>
Cc: Arnd Bergmann <[e-mail]>
Cc: Lee Jones <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/video/fbdev/mx3fb.c

···
 static void sdc_disable_channel(struct mx3fb_info *mx3_fbi)
 {
 	struct mx3fb_data *mx3fb = mx3_fbi->mx3fb;
-	uint32_t enabled;
 	unsigned long flags;
 
 	if (mx3_fbi->txd == NULL)
···
 
 	spin_lock_irqsave(&mx3fb->lock, flags);
 
-	enabled = sdc_fb_uninit(mx3_fbi);
+	sdc_fb_uninit(mx3_fbi);
 
 	spin_unlock_irqrestore(&mx3fb->lock, flags);
 
···
 
 /**
  * mx3fb_set_fix() - set fixed framebuffer parameters from variable settings.
- * @info:	framebuffer information pointer
+ * @fbi:	framebuffer information pointer
  * @return:	0 on success or negative error code on failure.
  */
 static int mx3fb_set_fix(struct fb_info *fbi)
···
 	struct fb_fix_screeninfo *fix = &fbi->fix;
 	struct fb_var_screeninfo *var = &fbi->var;
 
-	strncpy(fix->id, "DISP3 BG", 8);
+	memcpy(fix->id, "DISP3 BG", 8);
 
 	fix->line_length = var->xres_virtual * var->bits_per_pixel / 8;
 
···
 
 /**
  * mx3fb_blank() - blank the display.
+ * @blank:	blank value for the panel
+ * @fbi:	framebuffer information pointer
  */
 static int mx3fb_blank(int blank, struct fb_info *fbi)
 {
···
 /**
  * mx3fb_pan_display() - pan or wrap the display
  * @var:	variable screen buffer information.
- * @info:	framebuffer information pointer.
+ * @fbi:	framebuffer information pointer.
  *
  * We look only at xoffset, yoffset and the FB_VMODE_YWRAP flag
  */
···
 
 /**
  * mx3fb_init_fbinfo() - initialize framebuffer information object.
+ * @dev: the device
+ * @ops:	framebuffer device operations
  * @return:	initialized framebuffer structure.
  */
 static struct fb_info *mx3fb_init_fbinfo(struct device *dev,