PS3: gelic: code cleanup

Code cleanup:
 - Use appropriate prefixes for names instead of fixed 'gelic_net'
   so that objects of the functions, variables and constants can be estimated.
 - Remove definitions for IPSec offload to the gelic hardware.  This
   functionality is never supported on PS3.
 - Group constants with enum.
 - Use bitwise constants for interrupt status, instead of bit numbers to
   eliminate shift operations.
 - Style fixes.
Signed-off-by: Masakazu Mokuno <mokuno@sm.sony.co.jp>
Signed-off-by: Jeff Garzik <jeff@garzik.org>