drm/i915: Spell vga_switcheroo consistently

Currently everyone and their dog has their own favourite spelling
for vga_switcheroo. This makes it hard to grep dmesg for log entries
relating to vga_switcheroo. It also makes it hard to find related
source files in the tree.

vga_switcheroo.c uses pr_fmt "vga_switcheroo". Use that everywhere.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 2034438a..2c11b4e 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -821,7 +821,7 @@
 		return;
 
 	/*
-	 * Do not disable backlight on the vgaswitcheroo path. When switching
+	 * Do not disable backlight on the vga_switcheroo path. When switching
 	 * away from i915, the other client may depend on i915 to handle the
 	 * backlight. This will leave the backlight on unnecessarily when
 	 * another client is not activated.