net: marvell: mvpp2: Fix W=1 warning with !CONFIG_ACPI

rivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:7084:36: warning: ‘mvpp2_acpi_match’ defined but not used [-Wunused-const-variable=]
 7084 | static const struct acpi_device_id mvpp2_acpi_match[] = {
      |                                    ^~~~~~~~~~~~~~~~

Wrap the definition inside #ifdef/#endif.

Compile tested only.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>