[WebAssembly] Simplify check for emitting relocations

This is a small change I split of from a larger one
that simplifies the condition that need to be checked
when decided if we need to emit relocation and all the
things they depend on (symbols, etc).

Differential Revision: https://reviews.llvm.org/D40825

llvm-svn: 319789
diff --git a/lld/wasm/Driver.cpp b/lld/wasm/Driver.cpp
index 5601cec..66329ac 100644
--- a/lld/wasm/Driver.cpp
+++ b/lld/wasm/Driver.cpp
@@ -257,6 +257,8 @@
   Config->Sysroot = Args.getLastArgValue(OPT_sysroot);
   errorHandler().Verbose = Args.hasArg(OPT_verbose);
   ThreadsEnabled = Args.hasFlag(OPT_threads, OPT_no_threads, true);
+  if (Config->Relocatable)
+    Config->EmitRelocs = true;
 
   Config->InitialMemory = args::getInteger(Args, OPT_initial_memory, 0);
   Config->GlobalBase = args::getInteger(Args, OPT_global_base, 1024);