Remove unused abort_jump from task.pmc
Remove unused abort_jump from task.pmc

task.pmc contained a Parrot_jumb_buff that was used for setjmp in invoke
but never actually got longjumped to. Remove it to save some memory.

youprofit/parrot,FROGGS/parrot,FROGGS/parrot,tkob/parrot,tkob/parrot,tkob/parrot,tkob/parrot,FROGGS/parrot,parrot/parrot,FROGGS/parrot,FROGGS/parrot,FROGGS/parrot,parrot/parrot,youprofit/parrot,youprofit/parrot,tkob/parrot,FROGGS/parrot,parrot/parrot,youprofit/parrot,tkob/parrot,tkob/parrot,parrot/parrot,youprofit/parrot,parrot/parrot,FROGGS/parrot,youprofit/parrot,tkob/parrot,youprofit/parrot,youprofit/parrot