[Docs][ORCv2] GetForCurrentProcess now returns an Expected<std::unique_ptr>. NFC

[lhames]

LGTM. Thanks Jon!

llvm/docs/ORCv2.rst

 
 For example, to load the whole interface of a runtime library:
 
   .. code-block:: c++
 
     const DataLayout &DL = getDataLayout();
     auto &JD = ES.createJITDylib("main");
 
-    JD.addGenerator(DynamicLibrarySearchGenerator::Load("/path/to/lib"
-                                                        DL.getGlobalPrefix()));
+    if (auto DLSGOrErr = DynamicLibrarySearchGenerator::Load("/path/to/lib"
+                                                             DL.getGlobalPrefix()))
+      JD.addGenerator(std::move(*DLSGOrErr);
+    else
+      return DLSGOrErr.takeError();
 
     // IR added to JD can now link against all symbols exported by the library
     // at '/path/to/lib'.
     CompileLayer.add(JD, loadModule(...));
 
 Or, to expose an allowed set of symbols from the main process:
 
   .. code-block:: c++
 
     const DataLayout &DL = getDataLayout();
     MangleAndInterner Mangle(ES, DL);
 
     auto &JD = ES.createJITDylib("main");
 
     DenseSet<SymbolStringPtr> AllowList({
         Mangle("puts"),
         Mangle("gets")
       });
 
     // Use GetForCurrentProcess with a predicate function that checks the
     // allowed list.
-    JD.addGenerator(
-      DynamicLibrarySearchGenerator::GetForCurrentProcess(
+    JD.addGenerator(cantFail(DynamicLibrarySearchGenerator::GetForCurrentProcess(
           DL.getGlobalPrefix(),
-        [&](const SymbolStringPtr &S) { return AllowList.count(S); }));
+          [&](const SymbolStringPtr &S) { return AllowList.count(S); })));
 
     // IR added to JD can now link against any symbols exported by the process
     // and contained in the list.
     CompileLayer.add(JD, loadModule(...));
 
 Roadmap
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