makefile: add Bengal config support for display techpack

Add required changes to makefile and enable the config
keys for Bengal target compilation.

Change-Id: I7a27be5feffd132cbc35d4a7aa27521b6841e2fe
Signed-off-by: Jayaprakash <jmadiset@codeaurora.org>

config/bengaldispconf.h

@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2019, The Linux Foundation. All rights reserved.
+ */
+
+#define CONFIG_DRM_MSM 1
+#define CONFIG_DRM_MSM_SDE 1
+#define CONFIG_SYNC_FILE 1
+#define CONFIG_DRM_MSM_DSI 1
+#define CONFIG_DSI_PARSER 1
+#define CONFIG_DRM_MSM_REGISTER_LOGGING 1
+#define CONFIG_DRM_SDE_EVTLOG_DEBUG 1
+#define CONFIG_QCOM_MDSS_PLL 1
+#define CONFIG_MSM_SDE_ROTATOR 1
+#define CONFIG_MSM_SDE_ROTATOR_EVTLOG_DEBUG 1