RFR: JDK-8216059: nsk_jvmti_parseoptions still has dependency on tilde separator

[Gary Adams]

The test/hotspot/jtreg/vmTestbase/vm/mlvm tests were missed when the 
parser was updated for
JDK-8211343. Those tests use tilde (~) as an option separator.

Here's a quick fix to add tilde back as an option separator. Testing is 
in progress.

diff --git 
a/test/hotspot/jtreg/vmTestbase/nsk/share/jvmti/jvmti_tools.cpp 
b/test/hotspot/jtreg/vmTestbase/nsk/share/jvmti/jvmti_tools.cpp
--- a/test/hotspot/jtreg/vmTestbase/nsk/share/jvmti/jvmti_tools.cpp
+++ b/test/hotspot/jtreg/vmTestbase/nsk/share/jvmti/jvmti_tools.cpp
@@ -221,7 +221,7 @@
      char *str = NULL;
      char *name = NULL;
      char *value = NULL;
-    const char *delimiters = " ,";
+    const char *delimiters = " ,~";
      if (options == NULL)
          return success;