Use the new kmem API functions in the channel and channel
related code.
Also delete the usage of kasprintf() since that must be paired
with a kfree(). Since the kasprintf() doesn't use the nvgpu kmem
machinery (and is Linux specific) instead use a small buffer
statically allocated on the stack.
Bug 1799159
Bug 1823380
Change-Id: Ied0183f57372632264e55608f56539861cc0f24f
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: http://git-master/r/1318312
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>