microblaze: Show return address from exception

Show also return address from exception which should
suggest where the problem is.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

microblaze: Fix stack usage in interrupt handler

Do not save registers below r1 stack pointer because
it is not checked by stack undeflow is not able to detect
it.

Signed-off-by: Michal Simek <mich

microblaze: Fix stack usage in interrupt handler

Do not save registers below r1 stack pointer because
it is not checked by stack undeflow is not able to detect
it.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

show more ...

microblaze: Support stack protection feature

Ensure that stack didn't rewrite important part
of u-boot.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

microblaze: Enable hardware exception by default

Enable hardware exception by default to be able to
handle it.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>