When exporting Maya Geometry to USD, the interpolation boundary settings are not repected.

**Describe the bug**
When a user has a mesh with subdivision complexity and an interpolation boundary that is not "edges and corner", exporting that geometry will still have the interpolation set to edges and corners on the resulting usd file.

this can cause the subdivision scheme to not smooth the objects as expected. th user would have to manually change that on the usd file afterwards.

**Steps to reproduce**
1. in Maya, Create a Plane primitive with 1 subdivision in height and width
2. on the Attribute Editor, under pPlaneShape1, OpenSubdiv Controls. set the vertex boundary to sharp edges. (setting the viewport to smooth mesh display should now show the plane as a disc.)
3. export the plane, make sure the subdivision method is set to catmull-clark
4. load the newly create usd file as a stage. note that the interpolation boundary is set to "edges and corners" instead of "edges only"

**Expected behavior**
The geometry boundary should be set to edges only.