microblaze: Increase max dtb size to 64K from 32K

This patch increases max dtb size to 64K from 32K. This fixes the issue  of
kernel hang with larger dtb of size greater than 32KB.

Signed-off-by: Siva Durga Prasad Paladugu <siva.durga.paladugu@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2 files changed