x86/intel_rdt: Merge cdp enable/disable calls

Now that the cdp_enable() and cdp_disable() calls are basically the same,
merge them into cdp_set_enabled(true/false).

All these functions are behind resctrl_arch_set_cdp_enabled(),
so the can take the rdt_hw_resource directly.

Signed-off-by: James Morse <james.morse@arm.com>