gianfar: Remove sysfs stubs for FIFOCFG and stashing

Removing the sysfs stubs for the Tx FIFOCFG and ATTRELI
(stashing) config registers, as these registers may only
be configured after a MAC reset, with the controller stopped
(i.e. during hw init, at probe() time).  The current sysfs
stubs allow on-the-fly updates of these registers (the locking
measures are useless and only add unecessary code).

Changing these registers is discouraged. Only the default values
will be used instead.

Moreover, the stashing (ATTRELI) configuration options were
effectively disabled (didn't get to the hw anyway if changed)
because the stashing device_flags (HAS_BD_STASHING|HAS_BUF_STASHING)
were "accidentally" cleared during probe().

Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/gianfar.txt

@@ -1,38 +1,8 @@
 The Gianfar Ethernet Driver
-Sysfs File description
 
 Author: Andy Fleming <afleming@freescale.com>
 Updated: 2005-07-28
 
-SYSFS
-
-Several of the features of the gianfar driver are controlled
-through sysfs files.  These are:
-
-bd_stash:
-To stash RX Buffer Descriptors in the L2, echo 'on' or '1' to
-bd_stash, echo 'off' or '0' to disable
-
-rx_stash_len:
-To stash the first n bytes of the packet in L2, echo the number
-of bytes to buf_stash_len.  echo 0 to disable.
-
-WARNING: You could really screw these up if you set them too low or high!
-fifo_threshold:
-To change the number of bytes the controller needs in the
-fifo before it starts transmission, echo the number of bytes to 
-fifo_thresh.  Range should be 0-511.
-
-fifo_starve:
-When the FIFO has less than this many bytes during a transmit, it
-enters starve mode, and increases the priority of TX memory
-transactions.  To change, echo the number of bytes to
-fifo_starve.  Range should be 0-511.
-
-fifo_starve_off:
-Once in starve mode, the FIFO remains there until it has this
-many bytes.  To change, echo the number of bytes to
-fifo_starve_off.  Range should be 0-511.
 
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