By Kevin Liffey LONDON (Reuters) -The strongly pro-Kremlin editor of Russia’s state-run RT news channel expressed anger on Saturday that enlistment officers were sending call-up papers to the wrong men, as frustration about a military mobilisation grew. Wednesday’s announcement of Russia’s first public mobilisation since World War Two, to shore up its faltering Ukraine war, has triggered a rush for the border, the arrests of over 1,000 protesters, and unease in the wider population. It is also attracting criticism from the Kremlin’s own official supporters, something almost unheard of in Russi…