gpu: host1x: select CONFIG_DMA_SHARED_BUFFER

Linking fails when dma-buf is disabled:

ld.lld: error: undefined symbol: dma_fence_release
>>> referenced by fence.c
>>> gpu/host1x/fence.o:(host1x_syncpt_fence_enable_signaling) in archive drivers/built-in.a
>>> referenced by fence.c
>>> gpu/host1x/fence.o:(host1x_fence_signal) in archive drivers/built-in.a
>>> referenced by fence.c
>>> gpu/host1x/fence.o:(do_fence_timeout) in archive drivers/built-in.a

Fixes: 687db2207b1b ("gpu: host1x: Add DMA fence implementation")
Signed-off-by: Arnd Bergmann <[e-mail]>
Reviewed-by: Mikko Perttunen <[e-mail]>
Signed-off-by: Thierry Reding <[e-mail]>

drivers/gpu/host1x/Kconfig

···
 config TEGRA_HOST1X
 	tristate "NVIDIA Tegra host1x driver"
 	depends on ARCH_TEGRA || (ARM && COMPILE_TEST)
+	select DMA_SHARED_BUFFER
 	select IOMMU_IOVA
 	help
 	  Driver for the NVIDIA Tegra host1x hardware.