Teach JNA to look for custom library paths

This is twall's jna git, commit a82a6ca (post release 4.1.0), with my path ("Get additional library paths from ldconfig on Linux"), commit f0ea52c, on top. Upstream PR: java-native-access/jna#478

Author: gohai

library/jna.jar

@@ -155,20 +155,11 @@ static protected void removePlugins() {
 
 
   static protected void buildLinuxPaths() {
-    // looking pretty dire, make sure at least LD_LIBRARY_PATH is set
-    // see https://github.com/twall/jna/issues/477
-    String ldPath = System.getenv("LD_LIBRARY_PATH");
-    if (ldPath == null || ldPath.length() == 0) {
-      System.out.println("Your system's LD_LIBRARY_PATH environment variable " +
-        "is not set, limiting the search for the video libraries to /usr/lib " +
-        "and /lib.");
-      // temporary hack for testing on Raspbian
-      if (System.getProperty("os.arch").equals("arm")) {
-        gstreamerLibPath = "/opt/vc/lib:/usr/local/lib:/lib/arm-linux-gnueabihf:/usr/lib/arm-linux-gnueabihf";
-      }
-    } else {
-      gstreamerLibPath = ldPath;
-    }
+    // the version of the JNA library bundled automatically tries
+    // all library paths known to the host system's ldconfig
+    // so we'd even catch locations like /usr/local/lib etc
+    // PL for upstream: https://github.com/twall/jna/pull/478
+    gstreamerLibPath = "";
     gstreamerPluginPath = "";
   }