[NCI] Removed the _XJIT_ prefix from JIT-generated call thunks.  Avoiding the STRING concatenation necessary to find the right thunk in the NCI hash speeds up startup time by more than 2%.
[NCI] Removed the _XJIT_ prefix from JIT-generated call thunks.  Avoiding the
STRING concatenation necessary to find the right thunk in the NCI hash speeds
up startup time by more than 2%.

git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@39862 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

tewk/parrot-select,fernandobrito/parrot,tkob/parrot,FROGGS/parrot,FROGGS/parrot,gitster/parrot,fernandobrito/parrot,tkob/parrot,gagern/parrot,FROGGS/parrot,FROGGS/parrot,fernandobrito/parrot,fernandobrito/parrot,parrot/parrot,tewk/parrot-select,youprofit/parrot,youprofit/parrot,fernandobrito/parrot,gitster/parrot,gagern/parrot,tkob/parrot,gitster/parrot,tkob/parrot,FROGGS/parrot,tkob/parrot,tkob/parrot,tewk/parrot-select,gitster/parrot,fernandobrito/parrot,tewk/parrot-select,tewk/parrot-select,youprofit/parrot,parrot/parrot,gitster/parrot,gagern/parrot,tewk/parrot-select,youprofit/parrot,tkob/parrot,youprofit/parrot,tewk/parrot-select,FROGGS/parrot,parrot/parrot,youprofit/parrot,gagern/parrot,gitster/parrot,gagern/parrot,FROGGS/parrot,fernandobrito/parrot,gagern/parrot,gitster/parrot,parrot/parrot,youprofit/parrot,gagern/parrot,tkob/parrot,FROGGS/parrot,parrot/parrot,youprofit/parrot