android: Fix const to non-const issue on android-tester

According to definition from hardware/bluetooth.h, the "val" field does
not have const modifier.

Fix clang errors like:

android/android-tester.c:760:14: error: initializing 'void *' with an
expression of type 'const char (*)[18]' discards qualifiers
[-Werror,-Wincompatible-pointer-types-discards-qualifiers]
eir: Add support for parsing DeviceID info
adapter: Add support for setting DID info from EIR
input: Add DualShock 4 detection

DS4 tries to connect right after pairing before SDP search completed
and no idev is present yet.
android/hal-msg: Add defines for each audio state
android/A2DP: Notify when audio state change to started
android/A2DP: Notify when audio state change to stopped
android/A2DP: Notify when audio state change to suspend
android/bluetooth: Fix sending device prop change event with no props
android/tester: Update property name use to start daemon
[travis-ci] Add configuration file
android: Fix GNU old-style struct field designator

This gives a warning on clang, that turns into an error due to -Werror.
tools: Add replacement for missing dbus_validate_path() on D-Bus 1.4

The replacement is based on code from D-Bus 1.6.