dt-bindings: clock: mediatek: Drop duplicate mediatek,mt6795-sys-clock.yaml

The compatible strings for mt6795 clocks are also documented in other
schemas:

"mediatek,mt6795-apmixedsys" in clock/mediatek,apmixedsys.yaml
"mediatek,mt6795-topckgen" in clock/mediatek,topckgen.yaml
"mediatek,mt6795-pericfg" in clock/mediatek,pericfg.yaml
"mediatek,mt6795-infracfg" in clock/mediatek,infracfg.yaml

The only difference is #reset-cells is not allowed in some of these,
but that aligns with actual users in .dts files.

Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
Acked-by: Conor Dooley <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring (Arm) <[email protected]>

Author: robherring