zgetrf_batched: fix discarding const warning

This MR solves the following warning:

/home/philippe/dev/chameleon/build/runtime/starpu/codelets/codelet_dgetrf_batched.c: In function ‘INSERT_TASK_dgetrf_panel_offdiag_batched’:
/home/philippe/dev/chameleon/build/runtime/starpu/codelets/codelet_dgetrf_batched.c:105:21: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
  105 |     clargs->cl_name = chameleon_codelet_name( clargs->cl_name, 1,
      |                     ^

Didn't look too much into it, I added the missing const, it still builds and the warning disappears, LGTM. But maybe there is another more clever way to fix it.

approved this merge request

mentioned in commit 0ac42d5c

merged

changed milestone to %Chameleon 1.3.0