Fix uninitialized value warnings.

Bug: 263274255
Test: presubmit; make tidy-system_subset
Change-Id: I1b6c7251ffa9760b1117a945460939b8eace8965
diff --git a/core/audio_request_manager.cc b/core/audio_request_manager.cc
index 3c0790e..e302d08 100644
--- a/core/audio_request_manager.cc
+++ b/core/audio_request_manager.cc
@@ -59,7 +59,7 @@
                                           uint32_t handle, bool enable,
                                           uint64_t bufferDuration,
                                           uint64_t deliveryInterval) {
-  uint32_t numSamples;
+  uint32_t numSamples = 0;
   return validateConfigureSourceArguments(handle, enable, bufferDuration,
                                           deliveryInterval, &numSamples) &&
          doConfigureSource(nanoapp->getInstanceId(), handle, enable, numSamples,
diff --git a/core/gnss_manager.cc b/core/gnss_manager.cc
index fccf38b..a2a5e83 100644
--- a/core/gnss_manager.cc
+++ b/core/gnss_manager.cc
@@ -295,7 +295,7 @@
   }
 
   auto callback = [](uint16_t type, void *data, void * /*extraData*/) {
-    uint16_t reportEventType;
+    uint16_t reportEventType = 0;
     if (!getReportEventType(static_cast<SystemCallbackType>(type),
                             &reportEventType) ||
         !EventLoopManagerSingleton::get()
@@ -721,7 +721,7 @@
   while (!mStateTransitions.empty()) {
     const auto &stateTransition = mStateTransitions.front();
 
-    size_t requestIndex;
+    size_t requestIndex = 0;
     bool hasRequest =
         nanoappHasRequest(stateTransition.nanoappInstanceId, &requestIndex);