tools/power turbostat: Add Android support for MSR device handling

It uses /dev/msrN device paths on Android instead of /dev/cpu/N/msr,
updates error messages and permission checks to reflect the Android
device path, and wraps platform-specific code with #if defined(ANDROID)
to ensure correct behavior on both Android and non-Android systems.
These changes improve compatibility and usability of turbostat on
Android devices.

Signed-off-by: Kaushlendra Kumar <kaushlendra.kumar@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>