target: display: Add capability to skip primary panel in lk

In the current implementation, we have support to select a
specific oem panel in bootloader but there is no support for
skipping the panel configuration completely. This change adds
support to skip the panel configuration in bootloader and is
useful when there is no panel configuration available in
bootloader.

Usage: fastboot oem select-display-panel none

Change-Id: I8c4d558717ee3fd5ced418996a6b26b06ae45837
diff --git a/target/apq8084/target_display.c b/target/apq8084/target_display.c
index ae3b071..3aa2379 100755
--- a/target/apq8084/target_display.c
+++ b/target/apq8084/target_display.c
@@ -394,6 +394,11 @@
 
 	panel_name += strspn(panel_name, " ");
 
+	if (!strcmp(panel_name, NO_PANEL_CONFIG)) {
+		dprintf(INFO, "Skip panel configuration\n");
+		return;
+	}
+
 	if (!strcmp(panel_name, HDMI_PANEL_NAME)) {
 		dprintf(INFO, "%s: HDMI is primary\n", __func__);
 		return;