RFR: 8245623: Remove unused code in sun/nio/fs after Solaris removal

[Claes Redestad]

Hi,

a small cleanup of code left unused in nio/fs after the Solaris removal

Bug:    https://bugs.openjdk.java.net/browse/JDK-8245623
Webrev: http://cr.openjdk.java.net/~redestad/8245623/open.00/

Testing: tier1

Thanks!

/Claes