PINE64

Finally got it done.

First I sorted out the adb connection issue. I tried different combinations of USB ports in my computer until one eventually worked. 
Then I cleaned out all the "Set Orientation" apps.
Then I did the following.
adb pull /system/build.prop
vi build.prop
       ro.sf.fakerotation=false
       ro.sf.hwrotation=90
       save and exit
adb root
adb remount
adb push build.prop /system/build.prop
adb shell "setprop persist.demo.hdmirotation portrait"
adb reboot

Great! Also, thanks for posting the solution.