Replace flash_driver callback with pointer to command_registration.
Eliminates all related routines and allows drivers to omit commands.

Replace flash_driver callback with pointer to command_registration.
Eliminates all related routines and allows drivers to omit commands.

Eliminates 'nand_cmd' global variable.

Eliminates 'flash_cmd' global variable.

Changes the jtag_interface->register_callbacks field to a list of
commands to be registered.  Changes callback to invocation of
register_commands() with that command registration list.  Removes all
JTAG interface driver register_command callback functions, which the
previous commits had converted into identical calls.

Use register_commands() with command registration array.

Use register commands with command registration array.

Use register_commands() with command registration array.

Use register_commands() with a command registration array.

Use register_commands() with command registration array.

Use register_commands() with command registration array.

Use register_commands() with a command registration array.

Use register_commands() with command registration array.
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This module was broken by previous changes, but no one has complained.
Are there still users for this modules?

Uses register_commands() with command registration array.

Use register_commands() with command_registration array.

Remove register_callbacks from pld_device structure, using an array
of command_registration records instead.

Updates core PLD and virtex2 commands to use register_commands().

Use register_commands() for registering {,x}svf commands.

Converts server directory to use new command registration paradigm.

Use register_commands() for logging callbacks.  Improve help and add
proper usage.

Use table instead of individual calls.  Add proper usage information.

Use register_commands() for top-level version and init command.

Use the new command registration chaining capabilities to eliminate
the foo_register_commands helper, folding its remaining command
handler setup into the hello_command_handlers registration array.

Use new register_commands() with command registration table.