iconv, localedef: avoid floating point rounding differences [BZ #24372]

Two cases of "int * 1.4" may result in imprecise results, which
in at least one case resulted in i686 and x86-64 producing
different locale files.  This replaced that floating point multiply
with integer operations.  While the hash table margin is increased
from 40% to 50%, testing shows only 2% increase in overall size
of the locale archive.

https://bugzilla.redhat.com/show_bug.cgi?id=1311954



Reviewed-by: Carlos O'Donell <carlos@redhat.com>