device: Add RenderScript default implementation
device: Add RenderScript default implementation

Bug: 37035983

  - OVERRIDE_RS_DRIVER is moved from libRS_internal to the default
  implmentation. In order for GPU driver to work on legacy devices, the
  default implementation needs to be part of PRODUCT_PACKAGES.

Test: mm
Test: CTS tests pass on Bullhead, and confirm GPU driver is working.
Change-Id: I72e6d5a36b267d77412801f9c02894a8af643d84
Signed-off-by: D. Andrei Măceș <0c53c7310db0d5ac2309cb35536eca37e951530f@nd.edu>

maruos/android_device_lge_hammerhead,maruos/android_device_lge_hammerhead,maruos/android_device_lge_hammerhead,maruos/android_device_lge_hammerhead