drm/i915: release mutex in i915_gem_init()'s error path
drm/i915: release mutex in i915_gem_init()'s error path

Found with smatch.

Signed-off-by: Mika Kuoppala <cd221c71e765d1ce593d15b204fee351fb09fd98@intel.com>
Signed-off-by: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>

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