[PATCH v3] Add support for the more recent Davicom DM9000A and DM9000

[Juergen Beisert]

The current Davicom DM9000 support covers the DM9000E device only. This patch
series adds support for the more recent DM9000A and DM9000B variants.
The DM9000E variant is still supported.

Tested on Mini2440 and scb9328 with the DM9000E variant and Mini6410 with the
DM9000A variant.

This is v3 of the patch series. It now uses the dev_* functions to output
debug or status messages, fixes some typos, cut timeout values and disables
the DM9k device on halt.

Comments are welcome.