zorro: Fix address space collision message with RAM expansion boards

zorro: Fix address space collision message with RAM expansion boards

When booting Linux on an Amiga with BigRAMPlus Zorro expansion board:

    zorro: Address space collision on device Zorro device 12128600 (Individual Computers) [??? 0x50000000-]

This happens because the address space occupied by the BigRAMPlus Zorro
device is already in use, as it is part of system RAM.  Hence the
message is harmless.

Zorro memory expansion boards have the ERTF_MEMLIST flag set, which
tells AmigaOS to link the board's RAM into the free memory list.  While
we could skip registering the board resource if this flag is set, that
may cause issues with Zorro II RAM excluded in a memfile.

Hence fix the issue by just ignoring the error if ERTF_MEMLIST is set.

Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20200713072429.6182-1-geert@linux-m68k.org