How to enable the second SD card slot in fsl android BSP

[#1]

The default FSL android BSP support 1 SD card slot. If customer need to support more sd slot in android.Please reference below steps.
There are two steps need to set up.

1 device/fsl.git
NOTE: 1  change the fstab. 2194000 is the address of usdhc2.
            2  change the mount point in storage_list.xml
diff --git a/sabresd_6dq/fstab.freescale b/sabresd_6dq/fstab.freescale
index 7f23edb..1529a27 100644
--- a/sabresd_6dq/fstab.freescale
+++ b/sabresd_6dq/fstab.freescale
@@ -4,6 +4,7 @@
# specify MF_CHECK, and must come before any filesystems that do specify MF_CHECK

/devices/soc0/soc.0/2100000.aips-bus/2198000.usdhc/mmc_host /mnt/media_rw/extsd vfat defaults voldmanaged=extsd:auto
+/devices/soc0/soc.0/2100000.aips-bus/2194000.usdhc/mmc_host /mnt/media_rw/extsd_expand vfat defaults voldmanaged=extsd_expand:auto
/devices/soc0/soc.0/2100000.aips-bus/2184000.usb/ci_hdrc.0  /mnt/media_rw/udisk vfat defaults voldmanaged=udisk:auto
/dev/block/mmcblk3p5    /system      ext4    ro,barrier=1                                                                               wait,verify
/dev/block/mmcblk3p4    /data        ext4    nosuid,nodev,nodiratime,noatime,nomblk_io_submit,noauto_da_alloc,errors=panic    wait,encryptable=/dev/block/mmcblk3p9
diff --git a/sabresd_6dq/overlay/frameworks/base/core/res/res/xml/storage_list.xml b/sabresd_6dq/overlay/frameworks/base/core/res/res/xml/storage_list.xml
index 3639bdc..c3f5105 100644
--- a/sabresd_6dq/overlay/frameworks/base/core/res/res/xml/storage_list.xml
+++ b/sabresd_6dq/overlay/frameworks/base/core/res/res/xml/storage_list.xml
@@ -41,6 +41,10 @@
              android:storageDescription="@string/storage_sd_card"
              android:primary="false"
              android:removable="true" />
+    <storage android:mountPoint="/storage/extsd_expand"
+             android:storageDescription="@string/storage_sd_card"
+             android:primary="false"
+             android:removable="true" />
     <storage android:mountPoint="/storage/udisk"

2  system/core.git
NOTE: mkdir the mount point.

build@scmbld2:~/maddev_lp5.1_consolidate_ga_10_30/system/core/rootdir$ git diff
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 2211cc2..fac37c2 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -72,7 +72,9 @@ on init
     mkdir /storage 0751 root sdcard_r

     mkdir /mnt/media_rw/extsd 0755 system system
+    mkdir /mnt/media_rw/extsd_expand 0755 system system
     symlink /mnt/media_rw/extsd /storage/extsd
+    symlink /mnt/media_rw/extsd_expand /storage/extsd_expand
     mkdir /mnt/media_rw/udisk 0755 system system