Add empty LDFLAGS to sysconfig

Author: msimacek

graalpython/com.oracle.graal.python.test/src/tests/unittest_tags/test_sysconfig.txt

@@ -8,6 +8,7 @@
 *graalpython.lib-python.3.test.test_sysconfig.TestSysConfig.test_get_paths
 *graalpython.lib-python.3.test.test_sysconfig.TestSysConfig.test_get_platform
 *graalpython.lib-python.3.test.test_sysconfig.TestSysConfig.test_get_scheme_names
+*graalpython.lib-python.3.test.test_sysconfig.TestSysConfig.test_ldshared_value
 *graalpython.lib-python.3.test.test_sysconfig.TestSysConfig.test_main
 *graalpython.lib-python.3.test.test_sysconfig.TestSysConfig.test_platform_in_subprocess
 *graalpython.lib-python.3.test.test_sysconfig.TestSysConfig.test_srcdir_independent_of_cwd

graalpython/lib-graalpython/_sysconfig.py

@@ -85,6 +85,7 @@ def _get_posix_vars():
     g['CONFINCLUDEPY'] = get_python_inc()
     g['CPPFLAGS'] = '-I. -I' + get_python_inc()
     g['CFLAGS'] = "-Wno-unused-command-line-argument -stdlib=libc++ -DNDEBUG -O1 -DHPY_UNIVERSAL_ABI"
+    g['LDFLAGS'] = ""
     g['CCSHARED'] = "-fPIC"
     g['LDSHARED_LINUX'] = "%s -shared -fPIC" % __graalpython__.get_toolchain_path('CC')
     if darwin_native: