linux-user: add BLKSSZGET ioctl wrapper

This patch adds an ioctl definition for BLKSSZGET.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

linux-user/ioctls.h

@@ -74,6 +74,7 @@
      IOCTL(BLKFLSBUF, 0, TYPE_NULL)
      IOCTL(BLKRASET, 0, TYPE_INT)
      IOCTL(BLKRAGET, IOC_R, MK_PTR(TYPE_LONG))
+     IOCTL(BLKSSZGET, IOC_R, MK_PTR(TYPE_LONG))
 #ifdef FIBMAP
      IOCTL(FIBMAP, IOC_W | IOC_R, MK_PTR(TYPE_LONG))
 #endif