Fixed -Wshift-sign-overflow warning

Shifting a 1 bit into or past the sign bit is undefined behaviour.
Instead, just use the new VTK_ID_MIN constant.

Change-Id: If58da9863e2264c886957d214aa4086e4fb25c81
Merge topic 'Wshift-sign-overflow' into master

6beda6f0 Fixed -Wshift-sign-overflow warning