staging: ion: Fix ION_IOC_FREE compat ioctl

The compat ioctl for ION_IOC_FREE currently passes allocation data
instead of the free data. Correct this.

Cc: Colin Cross <ccross@android.com>
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
[jstultz: Folded in a small build fix]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>