Removing unused import

Author: ppisl

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/MMapModuleBuiltins.java

@@ -45,7 +45,6 @@
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
-import java.nio.channels.FileChannel.MapMode;
 import java.nio.channels.SeekableByteChannel;
 import java.nio.file.StandardOpenOption;
 import java.util.HashSet;