[hal,wpilib] Add support for second I2C port (#7878)

wpilibj/src/main/java/edu/wpi/first/wpilibj/I2C.java

@@ -20,10 +20,10 @@ import java.nio.ByteBuffer;
 public class I2C implements AutoCloseable {
   /** I2C connection ports. */
   public enum Port {
-    /** Onboard I2C port. */
-    kOnboard(0),
-    /** MXP (roboRIO MXP) I2C port. */
-    kMXP(1);
+    /** I2C Port 0. */
+    kPort0(0),
+    /** I2C Port 1. */
+    kPort1(1);
 
     /** Port value. */
     public final int value;