fix ENABLE_TREBLE build broken by commit af35aadb

Test: build marlin-eng with and without ENABLE_TREBLE
Change-Id: Ia8cd2c8b01e2e14557b65ae8ce9c9c4827f596f5
diff --git a/media/libaudiohal/StreamHalHidl.cpp b/media/libaudiohal/StreamHalHidl.cpp
index 3d63fea..2c6e564 100644
--- a/media/libaudiohal/StreamHalHidl.cpp
+++ b/media/libaudiohal/StreamHalHidl.cpp
@@ -148,7 +148,7 @@
             [&](Result r, const MmapBufferInfo& hidlInfo) {
                 retval = r;
                 if (retval == Result::OK) {
-                    native_handle *handle = hidlInfo.sharedMemory->handle();
+                    const native_handle *handle = hidlInfo.sharedMemory.handle();
                     if (handle->numFds > 0) {
                         info->shared_memory_fd = dup(handle->data[0]);
                         info->buffer_size_frames = hidlInfo.bufferSizeFrames;