mmc: dt-bindings: update Mediatek MMC bindings

Add description for mediatek,hs200-cmd-int-delay
Add description for mediatek,hs400-cmd-int-delay
Add description for mediatek,hs400-cmd-resp-sel-rising

Signed-off-by: Yong Mao <yong.mao@mediatek.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/mtk-sd.txt

@@ -21,6 +21,15 @@ Optional properties:
 - assigned-clocks: PLL of the source clock
 - assigned-clock-parents: parent of source clock, used for HS400 mode to get 400Mhz source clock
 - hs400-ds-delay: HS400 DS delay setting
+- mediatek,hs200-cmd-int-delay: HS200 command internal delay setting.
+				This field has total 32 stages.
+				The value is an integer from 0 to 31.
+- mediatek,hs400-cmd-int-delay: HS400 command internal delay setting
+				This field has total 32 stages.
+				The value is an integer from 0 to 31.
+- mediatek,hs400-cmd-resp-sel-rising:  HS400 command response sample selection
+				       If present,HS400 command responses are sampled on rising edges.
+				       If not present,HS400 command responses are sampled on falling edges.
 
 Examples:
 mmc0: mmc@11230000 {
@@ -38,4 +47,7 @@ mmc0: mmc@11230000 {
 	assigned-clocks = <&topckgen CLK_TOP_MSDC50_0_SEL>;
 	assigned-clock-parents = <&topckgen CLK_TOP_MSDCPLL_D2>;
 	hs400-ds-delay = <0x14015>;
+	mediatek,hs200-cmd-int-delay = <26>;
+	mediatek,hs400-cmd-int-delay = <14>;
+	mediatek,hs400-cmd-resp-sel-rising;
 };