x86: acpi: Add DMA descriptors for I2C1 on Intel Tangier

Intel Tangier SoC has a general purpose DMA which can serve to speed up
communications on SPI and I2C serial buses.

Provide DMA descriptors to utilize this capability in the future.

Note, I2C6, which is available to user, has no DMA request lines connected.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/include/asm/arch-tangier/acpi/southcluster.asl

@@ -222,6 +222,17 @@ Device (PCI0)
         {
             Return (STA_VISIBLE)
         }
+
+        Name (RBUF, ResourceTemplate()
+        {
+            FixedDMA(0x0009, 0x0000, Width32bit, )
+            FixedDMA(0x0008, 0x0001, Width32bit, )
+        })
+
+        Method (_CRS, 0, NotSerialized)
+        {
+            Return (RBUF)
+        }
     }
 
     Device (I2C6)