hw/mips/malta: Fix FPGA I/O region size

The FPGA present on the CoreCard has an I/O region 1MiB wide.

Refs:
- Atlas User’s Manual (Document Number: MD00005)
- Malta User’s Manual (Document Number: MD00048)

Fixes: ea85df72b60 ("mips_malta: convert to memory API")
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200905213049.761949-1-f4bug@amsat.org>

hw/mips/malta.c

@@ -578,7 +578,7 @@ static MaltaFPGAState *malta_fpga_init(MemoryRegion *address_space,
     memory_region_init_alias(&s->iomem_lo, NULL, "malta-fpga",
                              &s->iomem, 0, 0x900);
     memory_region_init_alias(&s->iomem_hi, NULL, "malta-fpga",
-                             &s->iomem, 0xa00, 0x10000 - 0xa00);
+                             &s->iomem, 0xa00, 0x100000 - 0xa00);
 
     memory_region_add_subregion(address_space, base, &s->iomem_lo);
     memory_region_add_subregion(address_space, base + 0xa00, &s->iomem_hi);