drm/i915/gvt: Fix the compiling error when CONFIG_DRM_I915_DEBUG_RUNTIME_PM=n

A compiling error was reported when CONFIG_DRM_I915_DEBUG_RUNTIME_PM=n.
Fix the problem by using the pre-defined macro.

Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220427212849.18109-2-zhi.a.wang@intel.comReviewed-by: Jani Nikula <jani.nikula@linux.intel.com>

drivers/gpu/drm/i915/intel_gvt.c

@@ -309,7 +309,9 @@ EXPORT_SYMBOL_NS_GPL(__intel_context_do_pin, I915_GVT);
 EXPORT_SYMBOL_NS_GPL(__intel_context_do_unpin, I915_GVT);
 EXPORT_SYMBOL_NS_GPL(intel_ring_begin, I915_GVT);
 EXPORT_SYMBOL_NS_GPL(intel_runtime_pm_get, I915_GVT);
+#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)
 EXPORT_SYMBOL_NS_GPL(intel_runtime_pm_put, I915_GVT);
+#endif
 EXPORT_SYMBOL_NS_GPL(intel_runtime_pm_put_unchecked, I915_GVT);
 EXPORT_SYMBOL_NS_GPL(intel_uncore_forcewake_for_reg, I915_GVT);
 EXPORT_SYMBOL_NS_GPL(intel_uncore_forcewake_get, I915_GVT);