drm/xe: Use intel_wakeref_t in intel_runtime_pm functions

Now intel_wakeref_t is a unsigned long and Xe KMD version of those
functions should use the same type, so changing from bool to
intel_wakeref_t.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>