ACPI / sysfs: Add support to allow leading "\" missing in trace_method_name.
ACPI / sysfs: Add support to allow leading "\" missing in trace_method_name.

Since _SB.PCI0 can be used as relative path from root and can be easily
converted into internal trace_method_name format, we allow users to specify
trace_method_name using relative paths from root.
Note this is useful for grub2 for which users failed to pass "\" from the
grub configuration file.

Signed-off-by: Lv Zheng <687b611ec106f085ac3db1fd0c8e91dc3509d58c@intel.com>
Signed-off-by: Rafael J. Wysocki <27ffc44a8ec6a212fba98cfc3246c6ce8ab131e0@intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs