microblaze: exception: move privileged instruction exception out of v5 ifdef

microblaze: exception: move privileged instruction exception out of v5 ifdef

The privileged instruction exception seems to have been introduced in
microblaze v7.00 along with MMU support, so having it wrapped in
MICROBLAZE_v5 ifdefs seems incorrect. Move it out of the ifdef, since all
recent microblaze versions support it.

Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Link: https://lore.kernel.org/r/20220213080925.1548411-1-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek <michal.simek@xilinx.com>