be2net: fix sleeping while atomic bugs in be_ndo_bridge_getlink

Partially revert commit b717241 ("be2net: replace polling with
sleeping in the FW completion path") w.r.t mcc mutex it introduces and the
use of usleep_range. The be2net be_ndo_bridge_getlink() callback is
called with rcu_read_lock, so this code has been broken for a long time.
Both the mutex_lock and the usleep_range can cause the issue Ian Kumlien
reported[1]. The call path is:
be_ndo_bridge_getlink -> be_cmd_get_hsw_config -> be_mcc_notify_wait ->
be_mcc_wait_compl -> usleep_range()

[1] https://lore.kernel.org/netdev/CAA85sZveppNgEVa_FD+qhOMtG_AavK9_mFiU+jWrMtXmwqefGA@mail.gmail.com/

Tested-by: Ian Kumlien <ian.kumlien@gmail.com>
Fixes: b717241 ("be2net: replace polling with sleeping in the FW completion path")
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250227164129.1201164-1-razor@blackwall.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: NikAleksandrov

drivers/net/ethernet/emulex/benet/be.h

@@ -562,7 +562,7 @@ struct be_adapter {
 	struct be_dma_mem mbox_mem_alloced;
 
 	struct be_mcc_obj mcc_obj;
-	struct mutex mcc_lock;	/* For serializing mcc cmds to BE card */
+	spinlock_t mcc_lock;	/* For serializing mcc cmds to BE card */
 	spinlock_t mcc_cq_lock;
 
 	u16 cfg_num_rx_irqs;		/* configured via set-channels */