ehea/ibm*: Move the IBM drivers

ehea/ibm*: Move the IBM drivers

Move the IBM drivers into drivers/net/ethernet/ibm/ and make the
necessary Kconfig and Makefile changes.

- Renamed ibm_new_emac to emac
- Cleaned up Makefile and Kconfig options which referred to
  IBM_NEW_EMAC to IBM_EMAC
- ibmlana driver is a National Semiconductor SONIC driver so
  it was not moved

CC: Christoph Raisch <[email protected]>
CC: Santiago Leon <[email protected]>
CC: Benjamin Herrenschmidt <[email protected]>
CC: David Gibson <[email protected]>
CC: Kyle Lucke <[email protected]>
CC: Michael Ellerman <[email protected]>
Signed-off-by: Jeff Kirsher <[email protected]>