drm/xe: Drop "_REG" suffix from CSFE_CHICKEN1

drm/xe: Drop "_REG" suffix from CSFE_CHICKEN1

We don't use this suffix on any other registers, and it isn't part of
the register's official name either, so drop it for consistency.

While at it, move the register definition slightly so that it isn't
separating RING_CMD_CCTL's definition from its fields.

Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20231214184659.2249559-11-matthew.d.roper@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>