mmc: host: OTA upgrade scenario support for multi fs combination

If fs is ext4, is_ext4 is true and cmdq_use_default_du_size is also true
but if fs is combination of multiple fs like ext4 and emmc,
cmdq_use_default_du_size should be set as false for non ext4 cases.

Test : FBEPolicy kernel vts test.

Change-Id: I0db34aa84ad7c164c1cc50d131b70729a293ed4f
Signed-off-by: Pruthvi Kurada <pkurada@codeaurora.org>