mlxsw: reg: Fix SPVMLR max record count

The num_rec field is 8 bit, so the maximal count number is 255.
This fixes vlans learning not being enabled for wider ranges than 255.

Fixes: a4feea74cd7a ("mlxsw: reg: Add Switch Port VLAN MAC Learning register definition")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/reg.h

@@ -1702,7 +1702,7 @@ static inline void mlxsw_reg_sfmr_pack(char *payload,
 #define MLXSW_REG_SPVMLR_ID 0x2020
 #define MLXSW_REG_SPVMLR_BASE_LEN 0x04 /* base length, without records */
 #define MLXSW_REG_SPVMLR_REC_LEN 0x04 /* record length */
-#define MLXSW_REG_SPVMLR_REC_MAX_COUNT 256
+#define MLXSW_REG_SPVMLR_REC_MAX_COUNT 255
 #define MLXSW_REG_SPVMLR_LEN (MLXSW_REG_SPVMLR_BASE_LEN + \
 			      MLXSW_REG_SPVMLR_REC_LEN * \
 			      MLXSW_REG_SPVMLR_REC_MAX_COUNT)