common: avb_verify: don't call mmc_switch_part for SD

mmc_switch_part() is used for switching between hw partitions
on eMMC (boot0, boot1, user, rpmb).
There is no need to do that for SD card.

This fixes the avb command usage on SD cards.

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Signed-off-by: Igor Opaniuk <igor.opaniuk@gmail.com>
Reviewed-by: Dragan Simic <dsimic@manjaro.org>
Link: https://lore.kernel.org/r/20240209192045.3961832-2-igor.opaniuk@foundries.io


Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>