Mostly revert "e1000/e1000e: Move PCI-Express device IDs over to e1000e"

The new e1000e driver is apparently not yet suitable for general use, so
mark it experimental, and re-instate all the PCI-Express device IDs in
the old and stable e1000 driver so that people (namely me) can continue
to use a driver that actually works.

Auke & co have been appraised of the situation.

Cc: Auke Kok <auke-jan.h.kok@intel.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>