allow setting classpath prefix when calling the mx extension python directly

Author: cosminbasca

mx.graalpython/mx_graalpython.py

@@ -119,7 +119,7 @@ def python(args, **kwargs):
     do_run_python(args, **kwargs)
 
 
-def do_run_python(args, extra_vm_args=None, env=None, jdk=None, extra_dists=None, **kwargs):
+def do_run_python(args, extra_vm_args=None, env=None, jdk=None, extra_dists=None, cp_prefix=None, cp_suffix=None, **kwargs):
     if not any(arg.startswith("--python.CAPI") for arg in args):
         capi_home = _get_capi_home()
         args.insert(0, "--python.CAPI=%s" % capi_home)
@@ -158,7 +158,7 @@ def do_run_python(args, extra_vm_args=None, env=None, jdk=None, extra_dists=None
 
     graalpython_args.insert(0, '--experimental-options=true')
 
-    vm_args += mx.get_runtime_jvm_args(dists, jdk=jdk)
+    vm_args += mx.get_runtime_jvm_args(dists, jdk=jdk, cp_prefix=cp_prefix, cp_suffix=cp_suffix)
 
     if not jdk:
         jdk = get_jdk()