Fix reading out of bounds of the collisions array. This fixes flying hedgehogs and not moving after explosion
fpc-compile:
ppc386 -Fl/usr/local/lib getrevnum.dpr
./getrevnum < /dev/null > revision.inc
ppc386 -B -Sd -Xs -OG -Or -O2 -Fl/usr/local/lib hw.dpr
ppc386 -B -Sd -Xs -OG -Or -O2 -Fl/usr/local/lib runhelper.dpr