drm/i915: use for_each_pipe loop to assign crtc_mask

This cleanup patch makes changes to use for_each_pipe loop
during bit-mask assignment of allowed crtc with encoder.

changes:
 - use BIT(i) macro instead of (1 << i) (Chris)
changes from V2:
 - use int for consistency (Jani)
changes from V3:
 - instead use enum pipe (Ville)
changes from V4:
 - drop DP/HDMI changes, as already part of patch from ville

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180919083126.31805-1-mahesh1.kumar@intel.com

drivers/gpu/drm/i915/intel_ddi.c

@@ -3751,6 +3751,7 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port)
 	struct intel_encoder *intel_encoder;
 	struct drm_encoder *encoder;
 	bool init_hdmi, init_dp, init_lspcon = false;
+	enum pipe pipe;
 
 
 	init_hdmi = (dev_priv->vbt.ddi_port_info[port].supports_dvi ||
@@ -3801,8 +3802,9 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port)
 	intel_encoder->type = INTEL_OUTPUT_DDI;
 	intel_encoder->power_domain = intel_port_to_power_domain(port);
 	intel_encoder->port = port;
-	intel_encoder->crtc_mask = (1 << 0) | (1 << 1) | (1 << 2);
 	intel_encoder->cloneable = 0;
+	for_each_pipe(dev_priv, pipe)
+		intel_encoder->crtc_mask |= BIT(pipe);
 
 	if (INTEL_GEN(dev_priv) >= 11)
 		intel_dig_port->saved_port_bits = I915_READ(DDI_BUF_CTL(port)) &