use getHostTriple instead of getDefaultTargetTriple in getClosestTargetForJIT

Get back getHostTriple.

For JIT compilation, use the host triple instead of the default
target: this fixes some JIT testcases that used to fail when the
compiler has been configured as a cross compiler.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147542 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Support/CommandLine.cpp

@@ -1373,6 +1373,7 @@ public:
        << "  Built " << __DATE__ << " (" << __TIME__ << ").\n"
 #endif
        << "  Default target: " << sys::getDefaultTargetTriple() << '\n'
+       << "  Host: " << sys::getHostTriple() << '\n'
        << "  Host CPU: " << CPU << '\n';
   }
   void operator=(bool OptionWasSpecified) {