ide-generic: remove ide_default_{io_base,irq}() inlines (take 3)

Replace ide_default_{io_base,irq}() inlines by legacy_{bases,irqs}[].

v2:
Add missing zero-ing of hws[] (caught during testing by Borislav Petkov).

v3:
Fix zero-oing of hws[] for _real_ this time.

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>