gpu: host1x: Add debug support

Add support for host1x debugging. Adds debugfs entries, and dumps
channel state to UART in case of stuck job.

Signed-off-by: Arto Merilainen <amerilainen@nvidia.com>
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de>
Tested-by: Thierry Reding <thierry.reding@avionic-design.de>
Tested-by: Erik Faye-Lund <kusmabite@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

drivers/gpu/host1x/Makefile

@@ -7,6 +7,7 @@ host1x-y = \
 	cdma.o \
 	channel.o \
 	job.o \
+	debug.o \
 	hw/host1x01.o
 
 obj-$(CONFIG_TEGRA_HOST1X) += host1x.o