Revert the part of r2762 where the command line code-page overrides the declared one.

The warning that the command line and declared CodePage are different is still printed
although there may not be anything actually wrong with that. And you may still wish to
know.

git-svn-id: http://svn.mkgmap.org.uk/mkgmap/trunk@2886 25d90789-57f7-4ee0-8453-03a3dfeeeb22