[PATCH v5.10-rt] rt: fix build issue in be2net

["Luis Claudio R. Goncalves" <lgoncalv@redhat.com>]

While working on v5.10.235-rt128-rc1 I noticed a build problem with
CONFIG_BE2NET enabled. Upon inspection I noticed commit 7cfae8627511
("be2net: fix sleeping while atomic bugs in be_ndo_bridge_getlink"),
from v5.10.235, which contains the following statement:

	return spin_unlock_bh(&adapter->mcc_lock);

The compiler complains when trying to expand the macro spin_unlock_bh()
in that context, requiring a fix similar to commit 386242acb15e ("rt: fix
build issue in at_hdmac"). This problem is specific to v5.10-rt.

Fixes: 7cfae8627511 ("be2net: fix sleeping while atomic bugs in be_ndo_bridge_getlink")
Signed-off-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
---

Sebastian, Steven, All,

Should I apply this solution in a RT update right after I release
v5.10.235-rt128 or should I backport the definition of rt locking
primitives from a newer PREEMPT_RT patch (say v5.15-rt or v6.1-rt)?


diff --git a/drivers/net/ethernet/emulex/benet/be_cmds.c b/drivers/net/ethernet/emulex/benet/be_cmds.c
index 9812a9a5d033..3068ccd37034 100644
--- a/drivers/net/ethernet/emulex/benet/be_cmds.c
+++ b/drivers/net/ethernet/emulex/benet/be_cmds.c
@@ -875,9 +875,10 @@ static int be_cmd_lock(struct be_adapter *adapter)
 /* Must be used only in process context */
 static void be_cmd_unlock(struct be_adapter *adapter)
 {
-	if (use_mcc(adapter))
-		return spin_unlock_bh(&adapter->mcc_lock);
-	else
+	if (use_mcc(adapter)) {
+		spin_unlock_bh(&adapter->mcc_lock);
+		return;
+	} else
 		return mutex_unlock(&adapter->mbox_lock);
 }