single stepping of multiple instructions (e.g., s/p,<count> and n/p).
db_print_loc_and_inst() already prints a newline on all arches although
it probably shouldn't.
Especially on SMP systems, single stepping tends to deadlock or panic
too quickly to be useful for anything except finding bugs in itself,
but with printing "itself" includes console drivers so it is useful
for generating stress tests for console drivers.
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