Use cutils/android_filesystem_config.h

private/android_filesystem_config.h is not available for
vndservicemanager.

Test: m -j
Test: BOARD_VNDK_VERSION m -j

Bug: 63135587
Change-Id: Iaf9911a519ebbb798184e93b2911d0e813e6026c
Merged-In: Iaf9911a519ebbb798184e93b2911d0e813e6026c