Add scale factor fields to HapticGenerator AIDL

Add support for haptic scale factors introduced to the HapticScale
parcelable defined at HapticGenerator.aidl.

Make sure the fields are forwarded to the os::HapticScale representation
to be used by ExternalVibratorUtils scaling function.

Bug: 356406324
Bug: 356406686
Flag: android.os.vibrator.haptics_scale_v2_enabled
Test: libvibrator_test
Change-Id: I310527f6a45f52e9dbe44090fc6102f3a69ebe23