[SYCL][XPTI] Fix dangling pointer (#8904)

Hoist a call to `packCallArguments` and conditionally obtain the data.
Fixes a dangling pointer issue.

Author: jchlanda

sycl/source/detail/plugin.hpp

@@ -177,10 +177,14 @@ class plugin {
     uint64_t CorrelationID = pi::emitFunctionBeginTrace(PIFnName);
     uint64_t CorrelationIDWithArgs = 0;
     unsigned char *ArgsDataPtr = nullptr;
+    using PackCallArgumentsTy =
+        decltype(packCallArguments<PiApiOffset>(std::forward<ArgsT>(Args)...));
+    auto ArgsData =
+        xptiTraceEnabled()
+            ? packCallArguments<PiApiOffset>(std::forward<ArgsT>(Args)...)
+            : PackCallArgumentsTy{};
     // TODO check if stream is observed when corresponding API is present.
     if (xptiTraceEnabled()) {
-      auto ArgsData =
-          packCallArguments<PiApiOffset>(std::forward<ArgsT>(Args)...);
       ArgsDataPtr = ArgsData.data();
       CorrelationIDWithArgs = pi::emitFunctionWithArgsBeginTrace(
           static_cast<uint32_t>(PiApiOffset), PIFnName, ArgsDataPtr, *MPlugin);