Change baroque static_cast<numeric type>(expr) to C style casts.

The semantics are the same, modulo mostly warning-filled pointer to
integer conversions.  There is no point making a simple cast stand out
more than the entire rest of the line (i.e. what the casted value is
being actually used for) with all those letters and brackets.

I have not verified whether all of these casts are actually necessary.
Also, I copied a variable rename from my previous cleanup PR to avoid
merge conflicts, and changed a series of former static_casts to u32 for
a %i argument to int (didn't touch %u, since that's painful either way).