drm/i915: Avoid leaking lpe audio platdev.data

drm/i915: Avoid leaking lpe audio platdev.data

The struct platform_device memdups the provided data pointer requiring
us to free the template we construct during lpe_audio_platdev_create():

unreferenced object 0xffff88026eafe400 (size 512):
  comm "insmod", pid 6850, jiffies 4295060179 (age 22.300s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000008e4a834c>] intel_audio_init+0x9/0x30 [i915]
    [<000000001360e195>] i915_driver_load+0x802/0x14e0 [i915]
    [<00000000ab3f0e99>] i915_pci_probe+0x29/0x70 [i915]
    [<0000000016330ee5>] pci_device_probe+0x9c/0x120
    [<000000000257d054>] driver_probe_device+0x307/0x470
    [<000000009f0a6cb6>] __driver_attach+0x98/0xe0
    [<0000000031b46e58>] bus_for_each_dev+0x57/0x80
    [<000000000e28239d>] bus_add_driver+0x1bd/0x260
    [<00000000abbe5161>] driver_register+0x52/0xc0
    [<000000005c6e23d4>] do_one_initcall+0x36/0x150
    [<00000000a55002f4>] do_init_module+0x56/0x1d7
    [<00000000e48f2217>] load_module+0x23c8/0x2910
    [<000000002b60bf61>] SyS_finit_module+0xb8/0xd0
    [<0000000041cbad96>] entry_SYSCALL_64_fastpath+0x17/0x70
    [<000000009f1d37ab>] 0xffffffffffffffff

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171209222133.31880-1-chris@chris-wilson.co.uk