mmc: rtsx_pci: Drop if block with always false condition

mmc: rtsx_pci: Drop if block with always false condition

rtsx_pci_sdmmc_drv_remove() is only called for a device after
rtsx_pci_sdmmc_drv_probe() returned 0. In that case platform_set_drvdata()
was called with a non-NULL value and so platform_get_drvdata()
won't return NULL.

Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230727070051.17778-16-frank.li@vivo.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>