cxgb4: remove unneeded if-null-free check

Eliminate the following coccicheck warning:

drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c:529:3-9: WARNING:
 NULL check before some freeing functions is not needed.
drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c:533:2-8: WARNING:
 NULL check before some freeing functions is not needed.
drivers/net/ethernet/chelsio/cxgb4/cxgb4_cudbg.c:161:2-7: WARNING:
 NULL check before some freeing functions is not needed.
drivers/net/ethernet/chelsio/cxgb4/clip_tbl.c:327:3-9: WARNING:
 NULL check before some freeing functions is not needed.
Signed-off-by: Qiheng Lin <linqiheng@huawei.com>
Link: https://lore.kernel.org/r/20210409115339.4598-1-linqiheng@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/chelsio/cxgb4/clip_tbl.c

@@ -323,7 +323,6 @@ void t4_cleanup_clip_tbl(struct adapter *adap)
 	struct clip_tbl *ctbl = adap->clipt;
 
 	if (ctbl) {
-		if (ctbl->cl_list)
 		kvfree(ctbl->cl_list);
 		kvfree(ctbl);
 	}

drivers/net/ethernet/chelsio/cxgb4/cxgb4_cudbg.c

@@ -157,7 +157,6 @@ static int cudbg_alloc_compress_buff(struct cudbg_init *pdbg_init)
 
 static void cudbg_free_compress_buff(struct cudbg_init *pdbg_init)
 {
-	if (pdbg_init->compress_buff)
 	vfree(pdbg_init->compress_buff);
 }
 

drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c

@@ -524,12 +524,8 @@ struct cxgb4_tc_u32_table *cxgb4_init_tc_u32(struct adapter *adap)
 out_no_mem:
 	for (i = 0; i < t->size; i++) {
 		struct cxgb4_link *link = &t->table[i];
-
-		if (link->tid_map)
 		kvfree(link->tid_map);
 	}
-
-	if (t)
 	kvfree(t);
 
 	return NULL;