Don't put mines adjacent to the starting position instead of just not *on* the

Don't put mines adjacent to the starting position instead of just not *on* the
starting position. (FS#12387 by Ophir Lojkine)

Since in minesweeper one needs information about at least two positions to
deduce anything (unless the first position has no adjacent mines at all),
having mines adjacent to the starting position means the player has to
guess without any information, which is no different than having a chance
that the first position already has a mine. I don't think minesweeper is
meant to be a game of pure luck.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30994 a1c6a512-1295-4272-9138-f99709370657