Renamed product file back to sysdyn.product.

Tycho works just as well regardless of the product file name.

refs #6879

diff --git a/releng/org.simantics.sysdyn.rcp.product/org.simantics.sysdyn.product.product b/releng/org.simantics.sysdyn.rcp.product/sysdyn.product
similarity index 100%
rename from releng/org.simantics.sysdyn.rcp.product/org.simantics.sysdyn.product.product
rename to releng/org.simantics.sysdyn.rcp.product/sysdyn.product