hw/sd/omap_mmc: Use device_cold_reset() instead of device_legacy_reset()

The omap_mmc_reset() function resets its SD card via
device_legacy_reset().  We know that the SD card does not have a qbus
of its own, so the new device_cold_reset() function (which resets
both the device and its child buses) is equivalent here to
device_legacy_reset() and we can just switch to the new API.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210430222348.8514-1-peter.maydell@linaro.org

hw/sd/omap_mmc.c

@@ -318,7 +318,7 @@ void omap_mmc_reset(struct omap_mmc_s *host)
      * into any bus, and we must reset it manually. When omap_mmc is
      * QOMified this must move into the QOM reset function.
      */
-    device_legacy_reset(DEVICE(host->card));
+    device_cold_reset(DEVICE(host->card));
 }
 
 static uint64_t omap_mmc_read(void *opaque, hwaddr offset,