Fixes a cppcheck warning. Possibly we should just convert
the array type to `long` since that's what oggpack_look()
returns, using negative values to report error.
However, none of the compared values are out of range
for either type so it doesn't really matter.
Signed-off-by: Erik de Castro Lopo <email@example.com>
Signed-off-by: Ralph Giles <firstname.lastname@example.org>