drm/i915: make hsw_{disable, restore}_lcpll static

These functions were added before the final PC8 implementation, and
their callers moved to intel_display.c during the code review.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 3d72b99..5fa58ad 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6157,8 +6157,8 @@
  * register. Callers should take care of disabling all the display engine
  * functions, doing the mode unset, fixing interrupts, etc.
  */
-void hsw_disable_lcpll(struct drm_i915_private *dev_priv,
-		       bool switch_to_fclk, bool allow_power_down)
+static void hsw_disable_lcpll(struct drm_i915_private *dev_priv,
+			      bool switch_to_fclk, bool allow_power_down)
 {
 	uint32_t val;
 
@@ -6208,7 +6208,7 @@
  * Fully restores LCPLL, disallowing power down and switching back to LCPLL
  * source.
  */
-void hsw_restore_lcpll(struct drm_i915_private *dev_priv)
+static void hsw_restore_lcpll(struct drm_i915_private *dev_priv)
 {
 	uint32_t val;