Add libnpt back into system.

It must be there for libjdwp to find it and load the debugger transport
correctly. This is a temporary fix while we are looking into loading libnpt
from the Runtime APEX.

Bug: 124498388
Test: adb forward tcp:5555 jdwp:`adb shell pidof com.android.email` && jdb -attach localhost:5555
Test: atest CtsJdwpTestCases
Change-Id: I644c092c2ad5f6c9669bdccc24c7953d3be6b328