dt-bindings: phy: imx8mq-usb: fix fsl,phy-tx-vboost-level-microvolt property

The ticket TKT0676370 shows the description of TX_VBOOST_LVL is wrong in
register PHY_CTRL3 bit[31:29].

011: Corresponds to a launch amplitude of 1.12 V.
010: Corresponds to a launch amplitude of 1.04 V.
000: Corresponds to a launch amplitude of 0.88 V.

After updated:

011: Corresponds to a launch amplitude of 0.844 V.
100: Corresponds to a launch amplitude of 1.008 V.
101: Corresponds to a launch amplitude of 1.156 V.

This will correct it accordingly.

Fixes: b2e75563dc39 ("dt-bindings: phy: imx8mq-usb: add phy tuning properties")
Cc: [e-mail]
Reviewed-by: Jun Li <[e-mail]>
Signed-off-by: Xu Yang <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml

···
   fsl,phy-tx-vboost-level-microvolt:
     description:
       Adjust the boosted transmit launch pk-pk differential amplitude
-    minimum: 880
-    maximum: 1120
+    enum: [844, 1008, 1156]
 
   fsl,phy-comp-dis-tune-percent:
     description: