qlcnic: dcb: default to returning -EOPNOTSUPP

Clang static analysis reports this issue
qlcnic_dcb.c:382:10: warning: Assigned value is
  garbage or undefined
  mbx_out = *val;
          ^ ~~~~

val is set in the qlcnic_dcb_query_hw_capability() wrapper.
If there is no query_hw_capability op in dcp, success is
returned without setting the val.

For this and similar wrappers, return -EOPNOTSUPP.

Fixes: 14d385b9 ("qlcnic: dcb: Query adapter DCB capabilities.")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/qlogic/qlcnic/qlcnic_dcb.h

@@ -51,7 +51,7 @@ static inline int qlcnic_dcb_get_hw_capability(struct qlcnic_dcb *dcb)
 	if (dcb && dcb->ops->get_hw_capability)
 		return dcb->ops->get_hw_capability(dcb);
 
-	return 0;
+	return -EOPNOTSUPP;
 }
 
 static inline void qlcnic_dcb_free(struct qlcnic_dcb *dcb)
@@ -65,7 +65,7 @@ static inline int qlcnic_dcb_attach(struct qlcnic_dcb *dcb)
 	if (dcb && dcb->ops->attach)
 		return dcb->ops->attach(dcb);
 
-	return 0;
+	return -EOPNOTSUPP;
 }
 
 static inline int
@@ -74,7 +74,7 @@ qlcnic_dcb_query_hw_capability(struct qlcnic_dcb *dcb, char *buf)
 	if (dcb && dcb->ops->query_hw_capability)
 		return dcb->ops->query_hw_capability(dcb, buf);
 
-	return 0;
+	return -EOPNOTSUPP;
 }
 
 static inline void qlcnic_dcb_get_info(struct qlcnic_dcb *dcb)
@@ -89,7 +89,7 @@ qlcnic_dcb_query_cee_param(struct qlcnic_dcb *dcb, char *buf, u8 type)
 	if (dcb && dcb->ops->query_cee_param)
 		return dcb->ops->query_cee_param(dcb, buf, type);
 
-	return 0;
+	return -EOPNOTSUPP;
 }
 
 static inline int qlcnic_dcb_get_cee_cfg(struct qlcnic_dcb *dcb)
@@ -97,7 +97,7 @@ static inline int qlcnic_dcb_get_cee_cfg(struct qlcnic_dcb *dcb)
 	if (dcb && dcb->ops->get_cee_cfg)
 		return dcb->ops->get_cee_cfg(dcb);
 
-	return 0;
+	return -EOPNOTSUPP;
 }
 
 static inline void qlcnic_dcb_aen_handler(struct qlcnic_dcb *dcb, void *msg)