lxfb: properly alloc cmap in all cases and don't leak the memory

We weren't properly allocating the cmap for depths greater than 8bpp,
which caused pain for things like DirectFB. Also, we never freed the cmap
memory upon module unload..

[[e-mail]: dropped unnecessary code and clean up patch]
[[e-mail]: add error checking and handling]
Signed-off-by: Andres Salomon <[e-mail]>
Cc: Jordan Crouse <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/video/geode/lxfb_core.c

···
 
 static int lxfb_set_par(struct fb_info *info)
 {
-	if (info->var.bits_per_pixel > 8) {
+	if (info->var.bits_per_pixel > 8)
 		info->fix.visual = FB_VISUAL_TRUECOLOR;
-		fb_dealloc_cmap(&info->cmap);
-	} else {
+	else
 		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
-		fb_alloc_cmap(&info->cmap, 1<<info->var.bits_per_pixel, 0);
-	}
 
 	info->fix.line_length = lx_get_pitch(info->var.xres,
 		info->var.bits_per_pixel);
···
 
 	info->pseudo_palette	= (void *)par + sizeof(struct lxfb_par);
 
+	if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
+		framebuffer_release(info);
+		return NULL;
+	}
+
 	info->var.grayscale	= 0;
 
 	return info;
···
 		pci_release_region(pdev, 3);
 	}
 
-	if (info)
+	if (info) {
+		fb_dealloc_cmap(&info->cmap);
 		framebuffer_release(info);
+	}
 
 	return ret;
 }
···
 	iounmap(par->vp_regs);
 	pci_release_region(pdev, 3);
 
+	fb_dealloc_cmap(&info->cmap);
 	pci_set_drvdata(pdev, NULL);
 	framebuffer_release(info);
 }