gk20a_err() and gk20a_warn() require a struct device pointer,
which is not portable across operating systems. The new nvgpu_err()
and nvgpu_warn() macros take struct gk20a pointer. Convert code
to use the more portable macros.
JIRA NVGPU-16
Change-Id: I50bab058076c6896acfc6fa82f78f52a949dd3cf
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/1457354
Reviewed-by: Alex Waterman <alexw@nvidia.com>