arm64: dts: dwc3: description of incr burst type

Add description of 'snps,incr-burst-type-adjustment' to binding
so that configuring devicetree.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
Signed-off-by: Pengbo Mu <pengbo.mu@nxp.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

Documentation/devicetree/bindings/usb/dwc3.txt

@@ -96,6 +96,11 @@ Optional properties:
 			enable periodic ESS TX threshold.
 
  - <DEPRECATED> tx-fifo-resize: determines if the FIFO *has* to be reallocated.
+ - snps,incr-burst-type-adjustment: Value for INCR burst type of GSBUSCFG0
+			register, undefined length INCR burst type enable and INCRx type.
+			When just one value, which means INCRX burst mode enabled. When
+			more than one value, which means undefined length INCR burst type
+			enabled. The values can be 1, 4, 8, 16, 32, 64, 128 and 256.
 
  - in addition all properties from usb-xhci.txt from the current directory are
    supported as well
@@ -108,4 +113,5 @@ dwc3@4a030000 {
 	reg = <0x4a030000 0xcfff>;
 	interrupts = <0 92 4>
 	usb-phy = <&usb2_phy>, <&usb3,phy>;
+	snps,incr-burst-type-adjustment = <1>, <4>, <8>, <16>;
 };