drm/i915/hdcp: HDCP2.x Refactoring to agnostic hdcp

There are more than 1 type of content protection security firmware.
Make the name generic
%s/_mei_/_

--v3
-Changing names to drop cp_fw to make naming more agnostic[Jani]

--v4
-remove header reference in intel_display_core.h [Uma]
-fix commit message and prefix drm [Uma]

Cc: Tomas Winkler <tomas.winkler@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Uma Shankar <uma.shankar@intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230316092927.668980-4-suraj.kandpal@intel.com

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

@@ -1409,7 +1409,7 @@ static int hdcp2_authenticate_port(struct intel_connector *connector)
 	return ret;
 }
 
-static int hdcp2_close_mei_session(struct intel_connector *connector)
+static int hdcp2_close_session(struct intel_connector *connector)
 {
 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
@@ -1433,7 +1433,7 @@ static int hdcp2_close_mei_session(struct intel_connector *connector)
 
 static int hdcp2_deauthenticate_port(struct intel_connector *connector)
 {
-	return hdcp2_close_mei_session(connector);
+	return hdcp2_close_session(connector);
 }
 
 /* Authentication flow starts from here */