drm/i915: be more strict about HAS_PCH_NOP() usage

HAS_PCH_NOP() implies a PCH platform without south display, not generic
disabled display. Prefer num_pipes == 0 for PCH independent checks.

Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180608123330.31003-5-jani.nikula@intel.com

drivers/gpu/drm/i915/intel_bios.c

@@ -1719,7 +1719,7 @@ void intel_bios_init(struct drm_i915_private *dev_priv)
 	const struct bdb_header *bdb;
 	u8 __iomem *bios = NULL;
 
-	if (HAS_PCH_NOP(dev_priv)) {
+	if (INTEL_INFO(dev_priv)->num_pipes == 0) {
 		DRM_DEBUG_KMS("Skipping VBT init due to disabled display.\n");
 		return;
 	}

drivers/gpu/drm/i915/intel_i2c.c

@@ -771,7 +771,7 @@ int intel_setup_gmbus(struct drm_i915_private *dev_priv)
 	unsigned int pin;
 	int ret;
 
-	if (HAS_PCH_NOP(dev_priv))
+	if (INTEL_INFO(dev_priv)->num_pipes == 0)
 		return 0;
 
 	if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))