gcc.target/cris/dbr-1.c: New test.

gcc.target/cris/dbr-1.c: New test.

Random spotting.  Exposes the missed benefit for delay-slot
filling of a splitter for indexed addressing mode (the [rN+M]
one).  To be considered for common instructions and perhaps only
for suitable M; at least +-63 is obvious (when there's a register
available) as both the original and the add fit in delay-slots.