selftests/bpf: shorten "Total insns/states" column names in veristat

selftests/bpf: shorten "Total insns/states" column names in veristat

In comparison mode the "Total " part is pretty useless, but takes
a considerable amount of horizontal space. Drop the "Total " parts.

Also make sure that table headers for numerical columns are aligned in
the same fashion as integer values in those columns. This looks better
and is now more obvious with shorter "Insns" and "States" column
headers.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20221103055304.2904589-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>