gpu: ion: Add missing argument to WARN call

The condition argument to the WARN call in ion_free is missing. Add the
argument to allow correct printing of warning message.

Change-Id: I158e1a583b7242b2c3209d6ce64dc0b771efeffe
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
1 file changed