arm64: dts: imx8mp-venice-gw74xx: fix TPM SPI frequency

The IMX8MPDS Table 37 [1] shows that the max SPI master read frequency
depends on the pins the interface is muxed behind with ECSPI2
muxed behind ECSPI2 supporting up to 25MHz.

Adjust the spi-max-frequency based on these findings.

[1] https://www.nxp.com/webapp/Download?colCode=IMX8MPIEC

Fixes: 531936b ("arm64: dts: imx8mp-venice-gw74xx: update to revB PCB")
Cc: stable@vger.kernel.org
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

Author: Gateworks

arch/arm64/boot/dts/freescale/imx8mp-venice-gw74xx.dts

@@ -201,7 +201,7 @@
 	tpm@0 {
 		compatible = "atmel,attpm20p", "tcg,tpm_tis-spi";
 		reg = <0x0>;
-		spi-max-frequency = <36000000>;
+		spi-max-frequency = <25000000>;
 	};
 };