qemublocktest: Disable testcases for all bitmap handling

qemublocktest: Disable testcases for all bitmap handling

Upcoming patches are going to rewrite and semantically modify how
bitmaps are handled during blockjobs. This is possible as incremental
backup is not yet fully enabled.

As the changes are going to be incompatible with any current test data
remove all test cases for bitmap handling during checkpoint deletion,
incremental backups, block commit, block copy, and bitmap validation
operations.

The tests will be gradually added back later after the code and
test-data is refactored.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>