drm/i915: use true,false for bool variable in intel_crt.c

Fixes coccicheck warning:

drivers/gpu/drm/i915/display/intel_crt.c:1066:1-28: WARNING: Assignment of 0/1 to bool variable
drivers/gpu/drm/i915/display/intel_crt.c:928:2-29: WARNING: Assignment of 0/1 to bool variable
drivers/gpu/drm/i915/display/intel_crt.c:443:2-29: WARNING: Assignment of 0/1 to bool variable
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Ma Feng <mafeng.ma@huawei.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1578013959-31486-4-git-send-email-mafeng.ma@huawei.com

drivers/gpu/drm/i915/display/intel_crt.c

@@ -440,7 +440,7 @@ static bool ilk_crt_detect_hotplug(struct drm_connector *connector)
 		bool turn_off_dac = HAS_PCH_SPLIT(dev_priv);
 		u32 save_adpa;
 
-		crt->force_hotplug_required = 0;
+		crt->force_hotplug_required = false;
 
 		save_adpa = adpa = I915_READ(crt->adpa_reg);
 		DRM_DEBUG_KMS("trigger hotplug detect cycle: adpa=0x%x\n", adpa);
@@ -925,7 +925,7 @@ void intel_crt_reset(struct drm_encoder *encoder)
 		POSTING_READ(crt->adpa_reg);
 
 		DRM_DEBUG_KMS("crt adpa set to 0x%x\n", adpa);
-		crt->force_hotplug_required = 1;
+		crt->force_hotplug_required = true;
 	}
 
 }
@@ -1063,7 +1063,7 @@ void intel_crt_init(struct drm_i915_private *dev_priv)
 	/*
 	 * Configure the automatic hotplug detection stuff
 	 */
-	crt->force_hotplug_required = 0;
+	crt->force_hotplug_required = false;
 
 	/*
 	 * TODO: find a proper way to discover whether we need to set the the