[SYCL] Fix memory leak in program link (#6641)

This PR fixes the memory leak caused by missing the call to program
release.

Signed-off-by: Byoungro So <byoungro.so@intel.com>

Author: bso-intel

sycl/source/detail/program_impl.cpp

@@ -295,6 +295,12 @@ void program_impl::link(std::string LinkOptions) {
     if (!LinkOpts) {
       LinkOpts = LinkOptions.c_str();
     }
+
+    // Plugin resets MProgram with a new pi_program as a result of the call to "piProgramLink".
+    // Thus, we need to release MProgram before the call to piProgramLink.
+    if (MProgram != nullptr)
+      Plugin.call<PiApiKind::piProgramRelease>(MProgram);
+    
     RT::PiResult Err = Plugin.call_nocheck<PiApiKind::piProgramLink>(
         MContext->getHandleRef(), Devices.size(), Devices.data(), LinkOpts,
         /*num_input_programs*/ 1, &MProgram, nullptr, nullptr, &MProgram);