refactor SDE detection in cmake files (#4512,#4700)

- add a specific plugin configuration
- checks for sde,sg and pe libs, adds pthread,socketi and dl if found
- adds #define SDE64 on 64 bit platforms
add missing file
restore submodule version
Merge pull request #4521 from tbonfort/cmake-sde

Building SDE support on 64-bit Linux needs work.
print destination directory in cmake status message
update autotest submodule for dpi tests
update submodule
add support for scale-dependant legend rendering (#4725)

closes #4725
Deal with long/int issues when compiling on a 64-bit system. (#4521)
Merge branch 'master' of https://github.com/mapserver/mapserver