drm/i915/ttm: remove calc_ctrl_surf_instr_size

We only ever need to emit one ccs block copy command.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Ramalingam <C&lt;ramalingam.c@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220805132240.442747-1-matthew.auld@intel.com