Fix error caused by reference to local binding (#151789)

This change fixes one of the failures in
llvm/llvm-project#147321

Following code snippet:
`
for (const auto &[CategoryName, PropSet] : PSRegistry) {
        J.attributeObject(CategoryName, [&] {
                   for (const auto &[PropName, PropVal] : PropSet) {
`
causes a build warning that is emitted as an error.
error: reference to local binding 'PropSet' declared in enclosing lambda
expression

This is resolved by capturing PropSet in a local variable.

Thanks

Signed-off-by: Arvind Sudarsanam <[email protected]>

Author: asudarsa

llvm/lib/Frontend/Offloading/PropertySet.cpp

@@ -19,8 +19,9 @@ void llvm::offloading::writePropertiesToJSON(
   json::OStream J(Out);
   J.object([&] {
     for (const auto &[CategoryName, PropSet] : PSRegistry) {
+      auto PropSetCapture = PropSet;
       J.attributeObject(CategoryName, [&] {
-        for (const auto &[PropName, PropVal] : PropSet) {
+        for (const auto &[PropName, PropVal] : PropSetCapture) {
           switch (PropVal.index()) {
           case 0:
             J.attribute(PropName, std::get<uint32_t>(PropVal));