Fix problem with static link order with static clang and llvm

---
Signed-off-by: Michael Ferguson <mppf@users.noreply.github.com>

util/chplenv/chpl_llvm.py

@@ -630,6 +630,18 @@ def get_host_link_args():
         if host_platform == 'darwin':
             llvm_dynamic = False
 
+        shared_mode = run_command([llvm_config, '--shared-mode'])
+
+        if shared_mode.strip() == 'static':
+            llvm_dynamic = False
+
+        # Make sure to put clang first on the link line
+        # because depends on LLVM libraries
+        if llvm_dynamic:
+            system.append('-lclang-cpp')
+        else:
+            system.extend(clang_static_libs)
+
         libdir = run_command([llvm_config, '--libdir'])
         if libdir:
             libdir = libdir.strip()
@@ -642,10 +654,6 @@ def get_host_link_args():
         if ldflags:
             system.extend(filter_llvm_link_flags(ldflags.split()))
 
-        if llvm_dynamic:
-            system.append('-lclang-cpp')
-        else:
-            system.extend(clang_static_libs)
 
     elif llvm_val == 'bundled':
         # Link statically for now for the bundled configuration