arm64: dts: exynos: gs101: ufs: add dma-coherent property

ufs-exynos driver configures the sysreg shareability as
cacheable for gs101 so we need to set the dma-coherent
property so the descriptors are also allocated cacheable.

This fixes the UFS stability issues we have seen with
the upstream UFS driver on gs101.

Fixes: 4c65d70 ("arm64: dts: exynos: gs101: Add ufs and ufs-phy dt nodes")
Cc: [email protected]
Suggested-by: Will McVicker <[email protected]>
Signed-off-by: Peter Griffin <[email protected]>
Tested-by: Will McVicker <[email protected]>
Tested-by: André Draszik <[email protected]>
Reviewed-by: André Draszik <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Krzysztof Kozlowski <[email protected]>

Author: petegriffin

arch/arm64/boot/dts/exynos/google/gs101.dtsi

@@ -1371,6 +1371,7 @@
 				 <&cmu_hsi2 CLK_GOUT_HSI2_SYSREG_HSI2_PCLK>;
 			clock-names = "core_clk", "sclk_unipro_main", "fmp",
 				      "aclk", "pclk", "sysreg";
+			dma-coherent;
 			freq-table-hz = <0 0>, <0 0>, <0 0>, <0 0>, <0 0>, <0 0>;
 			pinctrl-0 = <&ufs_rst_n &ufs_refclk_out>;
 			pinctrl-names = "default";