Replace kfree with nvgpu_free in error handling path in
gk20a_alloc_channel_gpfifo where the gpfifo pipe buffer is being
allocated, because it's allocated with nvgpu_alloc.
Jira DNVGPU-21
Change-Id: I73100394b67da2ab064e4e9df6b430d818abce56
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: http://git-master/r/1182401
GVS: Gerrit_Virtual_Submit
Reviewed-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-by: Vijayakumar Subbu <vsubbu@nvidia.com>