device-common: Set lcd_density to 400

Default lcd_density is not working for us anymore.
Set it explicitly to a reasonable value.

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
diff --git a/device-common.mk b/device-common.mk
index feccdf0..75e17b8 100644
--- a/device-common.mk
+++ b/device-common.mk
@@ -53,6 +53,7 @@
     debug.sf.no_hw_vsync=1 \
     hwc.drm.use_framebuffer_target=1 \
     hwc.drm.use_overlay_planes=0 \
+    ro.sf.lcd_density=400 \
     ro.opengles.version=196609
 
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