x86: tangier: Fix off-by-one error when preparing CSRT

Intel iDMA 32-bit controller has 17 bits for the maximum block size value.
Due to nature of the binary number representation the maximum value is
2^17 - 1. The original code misses the latter part in equation.

Fixes: 5e99fde34a ("x86: tangier: Populate CSRT for shared DMA controller")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/cpu/tangier/acpi.c

@@ -95,7 +95,7 @@ static u32 acpi_fill_csrt_dma(struct acpi_csrt_group *grp)
 	si->dma_address_width = 32;
 	si->base_request_line = 0;
 	si->num_handshake_signals = 16;
-	si->max_block_size = 0x20000;
+	si->max_block_size = 0x1ffff;
 
 	return grp->length;
 }