json: Fix off-by-one assert check in next_state()
The assert checking if the value of lexer->state in next_state(),
which is used as an index to the 'json_lexer' array, incorrectly
checks for an index value less than or equal to ARRAY_SIZE(json_lexer).
Fix assert so that it just checks for an index less than the array size.
Signed-off-by: Liam Merwick <firstname.lastname@example.org>
Reviewed-by: Markus Armbruster <email@example.com>
Reviewed-by: Li Qiang <firstname.lastname@example.org>
Reviewed-by: Stefano Garzarella <email@example.com>
Signed-off-by: Markus Armbruster <firstname.lastname@example.org>