S60 version plugins have incorrect ordinals in Linux

S60 version plugins do not conform to regular DEF file rules as they always need to use DEF files whether or not def_files is configured. They have custom MMP_RULES block for this, which breaks linux makefile based builds. They also use single def file for multiple targets.

Possible solution could be something along these lines:

Remove custom defBlock from s60pluginbase.pri and add the following lines:
CONFIG += def_files
DEF_FILE = ..

This doesn't work as is, because def_files.prf always inserts $$TARGET into the DEF file name, which doesn't work for S60 version plugins, who all share single def file. Of course that file could be duplicated for each plugin, but that just seems wrong. Maybe some additional check needs to be introduced to def_files.prf to enable specifying the file name explicitly without automatic target appending?