drm/msm/adreno: Fix a reference leak in a6xx_gpu_init()

In the Linux kernel, the following vulnerability has been resolved: drm/msm/adreno: Fix a reference leak in a6xx_gpu_init() In a6xx_gpu_init(), node is obtained via of_parse_phandle(). While there was a manual of_node_put() at the end of the common path, several early error returns would bypass this call, resulting in a reference leak. Fix this by using the __free(device_node) cleanup handler to release the reference when the variable goes out of scope. Patchwork: https://patchwork.freedesktop.org/patch/700661/