starpu: Silent warnings to compile in -Werror mode

sopalin/starpu/codelet_blok_zadd.c

sopalin/starpu/codelet_blok_zgemmsp.c

sopalin/starpu/codelet_blok_zgetrfsp.c

sopalin/starpu/codelet_blok_zhetrfsp.c

sopalin/starpu/codelet_blok_zpotrfsp.c

sopalin/starpu/codelet_blok_zpxtrfsp.c

sopalin/starpu/codelet_blok_zscalo.c

sopalin/starpu/codelet_blok_zsytrfsp.c

sopalin/starpu/codelet_blok_ztrsmsp.c

sopalin/starpu/codelet_cblk_zadd.c

sopalin/starpu/codelet_cblk_zgemmsp.c

sopalin/starpu/codelet_cblk_zgetrfsp.c

sopalin/starpu/codelet_cblk_zhetrfsp.c

sopalin/starpu/codelet_cblk_zpotrfsp.c

sopalin/starpu/codelet_cblk_zpxtrfsp.c

sopalin/starpu/codelet_cblk_zsytrfsp.c

sopalin/starpu/codelet_template.c

sopalin/starpu/starpu_rhs.c

sopalin/starpu/starpu_ztrsm.c