scm, cma: dat max_lmr_block_size is 32 bit, verbs max_mr_size is 64 bit

scm, cma: dat max_lmr_block_size is 32 bit, verbs max_mr_size is 64 bit

mismatch of device attribute size restricts max_lmr_block_size to 32 bit
value. Add check, if larger then limit to 4G-1 until DAT v2 spec changes.

Consumers should use max_lmr_virtual_address for actual max
registration block size until attribute interface changes.

Signed-off-by: Arlin Davis <arlin.r.davis@intel.com>