BLOCK: removed an unnecessary include.

Signed-off-by: bert <bert.timmerman@xs4all.nl>
Moved a system include to global.h.

Signed-off-by: bert <bert.timmerman@xs4all.nl>
ENDBLK: removed an unnecessary include.

Signed-off-by: bert <bert.timmerman@xs4all.nl>
BLOCK: apply a cast for the endblk in dxf_block_init().

Signed-off-by: bert <bert.timmerman@xs4all.nl>