fix priority of debug_req and single step
Created by: silabs-PaulZ
Replaced the debug_ebrk_entry register add in #531 with debug_req_entry register. This will assert when debug entry is caused by debug_req at the time it preempts any instruction being decoded. This will fix the issues reported in #529 (closed)
Signed-off-by: Paul Zavalney paul.zavalney@silabs.com