gralloc: Fix a build error with NATIVE_COVERAGE=true

hardware/qcom/display/msm8996/libgralloc/alloc_controller.h:49:
error: undefined reference to 'vtable for gralloc::IAllocController'

Bug: 34196613
Test: make
Change-Id: I7d22f29ef9f566c01615f75baaa8557a7bbe3ec8
1 file changed
tree: e94321dd16ed9af3f62ba06ecf4d8a9b768621a6
  1. msm8084/
  2. msm8226/
  3. msm8909/
  4. msm8960/
  5. msm8994/
  6. msm8996/
  7. msmcobalt/
  8. Android.mk