Return ErrorOr from getSymbolAddress.

It can fail trying to get the section on ELF and COFF. This makes sure the
error is handled.

llvm-svn: 241366
diff --git a/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp b/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
index 98c6f5c..50eb87a 100644
--- a/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
+++ b/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
@@ -269,9 +269,10 @@
         ErrorOr<StringRef> Name = Sym.getName();
         if (!Name)
           continue;
-        uint64_t Addr;
-        if (Sym.getAddress(Addr))
+        ErrorOr<uint64_t> AddrOrErr = Sym.getAddress();
+        if (!AddrOrErr)
           continue;
+        uint64_t Addr = *AddrOrErr;
 
         uint64_t Size = P.second;
         // If we're not using the debug object, compute the address of the