The Georgia Board of Pardons and Paroles Thursday blocked the execution of Freddie Davis six hours before he was to die in the electric chair for raping and stabbing to death a woman in 1977. The five-member board suspended the execution for up to 90 days to decide whether Davis' life should be spared. Although the board could lift the suspension at any time, board chairman Wayne Snow said he expected it would take at least that long to make a decision. Davis, 30, would have been the second murderer put to death in the nation in two days and the 101st since resumption of capital punishment in 1977.