Use default libnfc-nci.conf if not found in vendor/etc

If libnfc-nci.conf is not installed in vendor/etc, use default
configuration file in system/etc on GSI.

Bug: 72080121
Test: Install GSI and remove vendor/etc/libnfc-nci.conf.
      Check if nfc is available in settings menu.

Change-Id: Icc6e0b1d2b29adacf085cfa68566b064e736d3fa