hw/arm/aspeed: don't make 'boot_rom' region 'nomigrate'

Currently we use memory_region_init_ram_nomigrate() to create
the "aspeed.boot_rom" memory region, and we don't manually
register it with vmstate_register_ram(). This currently
means that its contents are migrated but as a ram block
whose name is the empty string; in future it may mean they
are not migrated at all. Use memory_region_init_ram() instead.

Note that would be a cross-version migration compatibility break
for the "palmetto-bmc", "ast2500-evb" and "romulus-bmc" machines,
but migration is currently broken for them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20180420124835.7268-3-peter.maydell@linaro.org
diff --git a/hw/arm/aspeed.c b/hw/arm/aspeed.c
index 7088c90..aecb3c1 100644
--- a/hw/arm/aspeed.c
+++ b/hw/arm/aspeed.c
@@ -225,7 +225,7 @@
          * SoC and 128MB for the AST2500 SoC, which is twice as big as
          * needed by the flash modules of the Aspeed machines.
          */
-        memory_region_init_rom_nomigrate(boot_rom, OBJECT(bmc), "aspeed.boot_rom",
+        memory_region_init_rom(boot_rom, OBJECT(bmc), "aspeed.boot_rom",
                                fl->size, &error_abort);
         memory_region_add_subregion(get_system_memory(), FIRMWARE_ADDR,
                                     boot_rom);