RFR(S) 8001077: remove ciMethod::will_link

[Bharadwaj Yadavalli]

Trivial cleanup - http://cr.openjdk.java.net/~bharadwaj/8001077/webrev/

ciMethod::will_link actually returns is_loaded. A comment in the method 
states:

   // The link checks have been front-loaded into the get_method
   // call. This method (ciMethod::will_link()) will be removed
   // in the future.

This comment is there since the duke:0 changeset.

Removed will_link and changed all calls to is_loaded().