[crossfire] Patch: Fix map display errors for big faces

[Nicolas Weeger]

>
     
      Note that mapdata.c still contains lots of assert() statements. They did
     
     >
     
      help me to ensure the passed coordinates are valid. I'll remove them
     
     >
     
      before I commit.
     
     
I have nothing against assert, as long as compilation is (usually) in
release mode (ie assert does nothing). Quite the contrary, if there is a
Bad Thing that assert can detect, so much the better!
Of course you could also just LOG & abort().

Ryo