Use keyboard-translate-table coding

Use keyboard-translate-table coding
system property, not translation-table-for-input, for
vietnamese-viscii & al.
(translation-table-for-input): Set,
don't defvar, and make permanent-local.
(ucs-unify-8859, ucs-unify-8859, ucs-fragment-8859): Add/remove
set-buffer-major-mode-hook, not quail-activate-hook.
(ucs-set-table-for-input): Renamed from ucs-quail-activate.
(ucs-unify-8859, ucs-unify-8859, ucs-fragment-8859): Setup
keyboard-translate-table, not translation-table-for-input.
Modify set-buffer-major-mode-hook, not quail-activate-hook.
(ucs-fragment-8859): Don't use translation-table-for-input coding
system property.
(ucs-quail-activate): Deleted.
(ucs-set-table-for-input): New.
(ucs-minibuffer-setup): Use it.