arm64: dts: marvell: samsung-coreprimevelte: Increase touchscreen voltage

arm64: dts: marvell: samsung-coreprimevelte: Increase touchscreen voltage

The old 1.9V setting was found to be insufficient in certain
environments (in my case cold ones), causing the touchscreen to register
ghost touches and mostly ignore actual touches. Increase the voltage to
2.5V to correct the issue.

Fixes: ec958b5b18c8 ("arm64: dts: samsung,coreprimevelte: add touchscreen")
Acked-by: Karel Balej <balejk@matfyz.cz>
Signed-off-by: Duje Mihanović <duje@dujemihanovic.xyz>