ide: limit legacy VLB host drivers to alpha, x86 and mips
These host drivers indirectly depend on CONFIG_IDE_ARCH_OBSOLETE_DEFAULTS=y
which is defined only on alpha, x86, ia64, m32r, mips and ppc32.
Moreover:
- on ia64 there is no ISA
- m32r is too new for VLB
- on ppc32 ISA is available only on PPC_CHRP (no default IDE ports)
and PPC_PREP (marked as BROKEN)
[ the common sense tells me that VLB was only used on x86 but there
are urban legends that one of these host drivers was needed on some
other arch - thus the extra care ]
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Bartlomiej Zolnierkiewicz