quotearg: pacify GCC better * modules/quotearg (Depends-on): Add minmax, stdint. * lib/quotearg.c: Include minmax.h, stdint.h. (nslots): Now int, as there seems little point to going to extra work merely to support the INT_MAX slot, which nobody ever uses. (quotearg_n_options): Redo size-overflow checks to pacify GCC and to catch (mostly-theoretical) ptrdiff_t problems too. This can be done via one comparison.