chelsio: Move the Chelsio drivers

Moves the drivers for the Chelsio chipsets into
drivers/net/ethernet/chelsio/ and the necessary Kconfig and Makefile
changes.

CC: Divy Le Ray <divy@chelsio.com>
CC: Dimitris Michailidis <dm@chelsio.com>
CC: Casey Leedom <leedom@chelsio.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>