BUG: Prevent DCMTK from trying to build unnecessary components

Some components of DCMTK are unnecessary to ITK, but enabled by default.
These should be explicitly disabled, preventing warnings if DCMTK fails
to build them.

Change-Id: Ib20b23bdfc369e6ec6a906598eb7e0f4fe86d24d
Merge topic 'DCMTK-warnings'

0f37ee0 BUG: Prevent DCMTK from trying to build unnecessary components