8054841: (process) ProcessBuilder leaks native memory

Reviewed-by: rriggs, alanb

src/solaris/native/java/lang/UNIXProcess_md.c

@@ -689,6 +689,7 @@ Java_java_lang_UNIXProcess_forkAndExec(JNIEnv *env,
     closeSafely(childenv[0]);
     closeSafely(childenv[1]);
 
+    releaseBytes(env, helperpath, phelperpath);
     releaseBytes(env, prog,       pprog);
     releaseBytes(env, argBlock,   pargBlock);
     releaseBytes(env, envBlock,   penvBlock);