arm: relinquish one IRQ priority reserved by kernel

The Cortex-M3/4 kernel was reserving priorities 0 and 1 for itself, but
was not registering any exception on priority 0. Only reserve priority 0
and use it for SVC and fault exceptions instead of priority 1.

Change-Id: Iff2405e27fd4bed4e49ab90ec2ae984f2c0a83a6
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
2 files changed