octeontx2-pf: handle otx2_mbox_get_rsp errors

octeontx2-pf: handle otx2_mbox_get_rsp errors

Adding error pointer check after calling otx2_mbox_get_rsp().

This is similar to the commit bd3110bc102a
("octeontx2-pf: handle otx2_mbox_get_rsp errors in otx2_flows.c").

Signed-off-by: Chenyuan Yang <chenyuan0y@gmail.com>
Fixes: 6c40ca957fe5 ("octeontx2-pf: Adds TC offload support")
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://patch.msgid.link/20250412183327.3550970-1-chenyuan0y@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>