Round beds require an odd number of probe points in
order to prevent erroneously truncating the mesh.
The adaptive mesh algorithm did not consider that and
as a result, it was possible to generate adaptive
meshes with even number of probe points.
This change fixes this by increasing the probe point
count by 1 in cases where the adaptive probe points
are even.
Signed-off-by: Mitko Haralanov <voidtrance@gmail.com>