Fix unused variable warnings.

Variables unused when specific flag is off.

Test: pass
Change-Id: I71638c1050ca655ef0932bb799d9777472a462d7
diff --git a/base/HidlInternal.cpp b/base/HidlInternal.cpp
index 9c0efbb..4f88be5 100644
--- a/base/HidlInternal.cpp
+++ b/base/HidlInternal.cpp
@@ -129,6 +129,7 @@
     }
 #else
     // No-op for user builds.
+    (void) instrumentationCallbacks;
     return;
 #endif
 }
@@ -139,6 +140,8 @@
     std::cmatch cm;
     std::regex e("^" + mInstrumentationLibPackage + "(.*).profiler.so$");
     if (std::regex_match(file->d_name, cm, e)) return true;
+#else
+    (void) file;
 #endif
     return false;
 }