So far, the various *-fs-factory.cpp files were #including the
corresponding *-fs.cpp files. This is surprising and hence could lead to
all kinds of problems). To fix this, provide proper headers for the
*-fs.cpp files.
This also makes code reuse via subclassing possible.
Since not all ports were tested, this will likely lead to a few
easy to fix compile regressions.
my implementation of romfs_seek is based on lseek, not on fseek,
so it returns the offset on successful completion, not 0, corrected
the check in RomfsStream::seek().
svn-id: r54151
