Avoid modulo operators against a power-of-two denominator.

* src/afcjk.c (af_hint_normal_stem), src/base/ftoutln.c
(ft_contour_has), src/cff/cffgload.c (cff_decoder_parse_charstrings)
<cff_op_vvcurveto, cff_op_hhcurveto, cff_op_hvcurveto>,
src/gxvalid/gxvcommn.c (GXV_32BIT_ALIGNMENT_VALIDATE),
src/gxvalid/gxvfeat.c (gxv_feat_setting_validate): Replace `%' with
`&' operator.
6 files changed