Revert "ENH: Updated constraints/restraints"

This reverts commit b3f01cd9.

src/sixDoFRigidBodyMotion/sixDoFRigidBodyMotion/constraints/sixDoFRigidBodyMotionConstraint/sixDoFRigidBodyMotionConstraint.C

@@ -60,7 +60,7 @@ bool Foam::sixDoFRigidBodyMotionConstraint::read
     const dictionary& sDoFRBMCDict
 )
 {
-    sDoFRBMCCoeffs_ = sDoFRBMCDict.subOrEmptyDict(type() + "Coeffs");
+    sDoFRBMCCoeffs_ = sDoFRBMCDict.subDict(type() + "Coeffs");
 
     return true;
 }

src/sixDoFRigidBodyMotion/sixDoFRigidBodyMotion/restraints/sixDoFRigidBodyMotionRestraint/sixDoFRigidBodyMotionRestraint.C

@@ -60,7 +60,7 @@ bool Foam::sixDoFRigidBodyMotionRestraint::read
     const dictionary& sDoFRBMRDict
 )
 {
-    sDoFRBMRCoeffs_ = sDoFRBMRDict.subOrEmptyDict(type() + "Coeffs");
+    sDoFRBMRCoeffs_ = sDoFRBMRDict;
 
     return true;
 }