net: mvneta: Fix CPU_MAP registers initialisation

The CPU_MAP register is duplicated for each CPUs at different addresses,
each instance being at a different address.

However, the code so far was using CONFIG_NR_CPUS to initialise the CPU_MAP
registers for each registers, while the SoCs embed at most 4 CPUs.

This is especially an issue with multi_v7_defconfig, where CONFIG_NR_CPUS
is currently set to 16, resulting in writes to registers that are not
CPU_MAP.

Fixes: c5aff18 ("net: mvneta: driver for Marvell Armada 370/XP network unit")
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: <stable@vger.kernel.org> # v3.8+
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvneta.c

@@ -949,7 +949,7 @@ static void mvneta_defaults_set(struct mvneta_port *pp)
 	/* Set CPU queue access map - all CPUs have access to all RX
 	 * queues and to all TX queues
 	 */
-	for (cpu = 0; cpu < CONFIG_NR_CPUS; cpu++)
+	for_each_present_cpu(cpu)
 		mvreg_write(pp, MVNETA_CPU_MAP(cpu),
 			    (MVNETA_CPU_RXQ_ACCESS_ALL_MASK |
 			     MVNETA_CPU_TXQ_ACCESS_ALL_MASK));