drm/i915/pmu: Fix wakeref leak in PMU busyness during reset

GuC PMU busyness gets gt wakeref if awake, but fails to release the
wakeref if a reset is in progress. Release the wakeref if it was
acquried successfully.

v2: Simplify the fix (Ashutosh)

Fixes: 2a67b18e ("drm/i915/pmu: Fix synchronization of PMU callback with reset")
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211207020239.43402-1-umesh.nerlige.ramappa@intel.com