s390/cmf: remove unneeded DMA zone allocation

The address of the measurement block can be anywhere in 64 bit
absolute space. See description of the schm instruction in the
Principles of Operation.

Therefore remove the GFP_DMA flag when allocating the block.

Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>