lib: textsearch: fix escapes in example code

[ Upstream commit 2105b52e30debe7f19f3218598d8ae777dcc6776 ]

This textsearch code example does not need the '\' escapes and they can
be misleading to someone reading the example. Also, gcc and sparse warn
that the "\%d" is an unknown escape sequence.

Fixes: 5968a70d ("textsearch: fix kernel-doc warnings and add kernel-api section")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>