Fix LLDB Android AArch64 GCC debug info build

Committing after fixing suggested changes and tested release/debug builds on 
x86_64-linux and arm/aarch64 builds.

Differential revision: https://reviews.llvm.org/D29042

llvm-svn: 293850
diff --git a/llvm/lib/Support/Unix/Path.inc b/llvm/lib/Support/Unix/Path.inc
index ecc9a2e..10e21af 100644
--- a/llvm/lib/Support/Unix/Path.inc
+++ b/llvm/lib/Support/Unix/Path.inc
@@ -180,7 +180,7 @@
       if (getprogpath(exe_path, argv0))
         return exe_path;
   }
-#elif defined(HAVE_DLFCN_H)
+#elif defined(HAVE_DLFCN_H) && defined(HAVE_DLADDR)
   // Use dladdr to get executable path if available.
   Dl_info DLInfo;
   int err = dladdr(MainAddr, &DLInfo);