Revert "Temporarily disable OMI's regress script"

This reverts commit bafbe6d8cf.

This change will re-enable regress script for OMI pbuild usage.

project.py

@@ -213,8 +213,8 @@ class ProjectOMI(Project):
         self.subProjects = ["omi", "pal"]
         self.makeDependencies = False
         self.projectName = "omi"
-        self.targets = "all tests"
-        self.postBuildSteps = []
+        self.targets = "clean"  # Do 'make clean' just do something (regress is all inclusive)
+        self.postBuildSteps = [ "./regress" ]
 
 class ProjectOMS(Project):
     ##