bpf: Replace 8 seq_puts() calls by seq_putc() calls

Single line breaks should occasionally be put into a sequence.
Thus use the corresponding function “seq_putc”.

This issue was transformed by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/e26b7df9-cd63-491f-85e8-8cabe60a85e5@web.de