Handle non-format partition in Vold

fsck_msdos will retun error code 8 when the partition is non-format.
Handle this error code and continue next partition in Vold.

Change-Id: I31499ccb16945ffbc67bdc92dfbc3ea71e82573a
Signed-off-by: Mateusz Nowak <mateusz.nowak@intel.com>
Signed-off-by: Zhiquan Liu <zhiquan.liu@intel.com>

fs/Vfat.cpp

@@ -108,6 +108,11 @@ status_t Check(const std::string& source) {
             errno = EIO;
             return -1;
 
+        case 8:
+            SLOGE("Filesystem check failed (no filesystem)");
+            errno = ENODATA;
+            return -1;
+
         default:
             SLOGE("Filesystem check failed (unknown exit code %d)", rc);
             errno = EIO;