Unbreak the build
priv/guest_ppc_toIR.c: In function disInstr_PPC:
priv/guest_ppc_toIR.c:20160:7: error: dis undeclared (first use in this function)
       dis.continueAt   = 0;
       ^


git-svn-id: svn://svn.valgrind.org/vex@2916 8f6e269a-dfd6-0310-a8e1-e2731360e62c