drm/vc4/vc4_hdmi: fill ASoC card owner

card->owner is a required property and since commit 81033c6b ("ALSA:
core: Warn on empty module") a warning is issued if it is empty. Fix lack
of it. This fixes following warning observed on RaspberryPi 3B board
with ARM 32bit kernel and multi_v7_defconfig:

------------[ cut here ]------------
WARNING: CPU: 1 PID: 210 at sound/core/init.c:207 snd_card_new+0x378/0x398 [snd]
Modules linked in: vc4(+) snd_soc_core ac97_bus snd_pcm_dmaengine bluetooth snd_pcm snd_timer crc32_arm_ce raspberrypi_hwmon snd soundcore ecdh_generic ecc bcm2835_thermal phy_generic
CPU: 1 PID: 210 Comm: systemd-udevd Not tainted 5.8.0-rc1-00027-g81033c6b #1087
Hardware name: BCM2835
[<c03113c0>] (unwind_backtrace) from [<c030bcb4>] (show_stack+0x10/0x14)
[<c030bcb4>] (show_stack) from [<c071cef8>] (dump_stack+0xd4/0xe8)
[<c071cef8>] (dump_stack) from [<c0345bfc>] (__warn+0xdc/0xf4)
[<c0345bfc>] (__warn) from [<c0345cc4>] (warn_slowpath_fmt+0xb0/0xb8)
[<c0345cc4>] (warn_slowpath_fmt) from [<bf02ff74>] (snd_card_new+0x378/0x398 [snd])
[<bf02ff74>] (snd_card_new [snd]) from [<bf11f0b4>] (snd_soc_bind_card+0x280/0x99c [snd_soc_core])
[<bf11f0b4>] (snd_soc_bind_card [snd_soc_core]) from [<bf12f000>] (devm_snd_soc_register_card+0x34/0x6c [snd_soc_core])
[<bf12f000>] (devm_snd_soc_register_card [snd_soc_core]) from [<bf165654>] (vc4_hdmi_bind+0x43c/0x5f4 [vc4])
[<bf165654>] (vc4_hdmi_bind [vc4]) from [<c09d660c>] (component_bind_all+0xec/0x24c)
[<c09d660c>] (component_bind_all) from [<bf15c44c>] (vc4_drm_bind+0xd4/0x174 [vc4])
[<bf15c44c>] (vc4_drm_bind [vc4]) from [<c09d6ac0>] (try_to_bring_up_master+0x160/0x1b0)
[<c09d6ac0>] (try_to_bring_up_master) from [<c09d6f38>] (component_master_add_with_match+0xd0/0x104)
[<c09d6f38>] (component_master_add_with_match) from [<bf15c588>] (vc4_platform_drm_probe+0x9c/0xbc [vc4])
[<bf15c588>] (vc4_platform_drm_probe [vc4]) from [<c09df740>] (platform_drv_probe+0x6c/0xa4)
[<c09df740>] (platform_drv_probe) from [<c09dd6f0>] (really_probe+0x210/0x350)
[<c09dd6f0>] (really_probe) from [<c09dd940>] (driver_probe_device+0x5c/0xb4)
[<c09dd940>] (driver_probe_device) from [<c09ddb38>] (device_driver_attach+0x58/0x60)
[<c09ddb38>] (device_driver_attach) from [<c09ddbc0>] (__driver_attach+0x80/0xbc)
[<c09ddbc0>] (__driver_attach) from [<c09db820>] (bus_for_each_dev+0x68/0xb4)
[<c09db820>] (bus_for_each_dev) from [<c09dc9f8>] (bus_add_driver+0x130/0x1e8)
[<c09dc9f8>] (bus_add_driver) from [<c09de648>] (driver_register+0x78/0x110)
[<c09de648>] (driver_register) from [<c0302038>] (do_one_initcall+0x50/0x220)
[<c0302038>] (do_one_initcall) from [<c03db544>] (do_init_module+0x60/0x210)
[<c03db544>] (do_init_module) from [<c03da4f8>] (load_module+0x1e34/0x2338)
[<c03da4f8>] (load_module) from [<c03dac00>] (sys_finit_module+0xac/0xbc)
[<c03dac00>] (sys_finit_module) from [<c03000c0>] (ret_fast_syscall+0x0/0x54)
Exception stack(0xeded9fa8 to 0xeded9ff0)
...
---[ end trace 6414689569c2bc08 ]---

Fixes: bb7d7856 ("drm/vc4: Add HDMI audio support")
Suggested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200701073949.28941-1-m.szyprowski@samsung.com

drivers/gpu/drm/vc4/vc4_hdmi.c

@@ -1117,6 +1117,7 @@ static int vc4_hdmi_audio_init(struct vc4_hdmi *hdmi)
 	card->num_links = 1;
 	card->name = "vc4-hdmi";
 	card->dev = dev;
+	card->owner = THIS_MODULE;
 
 	/*
 	 * Be careful, snd_soc_register_card() calls dev_set_drvdata() and