arm/acpi: simplify the description of PCI _CRS

arm/acpi: simplify the description of PCI _CRS

The original code defines a named object for the resource template but
then returns the resource template object itself; the resulted output
is like below:

Method (_CRS, 0, NotSerialized)  // _CRS: Current Resource Settings
{
    Name (RBUF, ResourceTemplate ()
    {
        WordBusNumber (ResourceProducer, MinFixed, MaxFixed, PosDecode,
            0x0000,             // Granularity
            0x0000,             // Range Minimum
            0x00FF,             // Range Maximum
            0x0000,             // Translation Offset
            0x0100,             // Length
            ,, )
        ......
    })
    Return (ResourceTemplate ()
    {
        WordBusNumber (ResourceProducer, MinFixed, MaxFixed, PosDecode,
            0x0000,             // Granularity
            0x0000,             // Range Minimum
            0x00FF,             // Range Maximum
            0x0000,             // Translation Offset
            0x0100,             // Length
            ,, )
        ......
    })
}

So the named object "RBUF" is actually useless. The more natural way
is to return RBUF instead, or simply drop RBUF definition.

Choose the latter one to simplify the code.

Signed-off-by: Heyi Guo <guoheyi@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20200204014325.16279-7-guoheyi@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>