Build with jdk-11

Index: src/java/org/lwjgl/opengl/Pbuffer.java
--- src/java/org/lwjgl/opengl/Pbuffer.java.orig
+++ src/java/org/lwjgl/opengl/Pbuffer.java
@@ -52,6 +52,7 @@ public final class Pbuffer extends DrawableGL {
 	/**
 	 * Indicates that Pbuffers can be created.
 	 */
+	@java.lang.annotation.Native
 	public static final int PBUFFER_SUPPORTED = 1 << 0;
 
 	/**
