ALSA: usb-audio: Add error checks for usb_driver_claim_interface() calls

There are a few calls of usb_driver_claim_interface() but all of those
miss the proper error checks, as reported by Coverity.  This patch
adds those missing checks.

Along with it, replace the magic pointer with -1 with a constant
USB_AUDIO_IFACE_UNUSED for better readability.

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1475943 ("Error handling issues")
Addresses-Coverity-ID: 1475944 ("Error handling issues")
Addresses-Coverity-ID: 1475945 ("Error handling issues")
Fixes: b1ce7ba6 ("ALSA: usb-audio: claim autodetected PCM interfaces all at once")
Fixes: e5779998 ("ALSA: usb-audio: refactor code")
Link: https://lore.kernel.org/r/202104051059.FB7F3016@keescook
Link: https://lore.kernel.org/r/20210406113534.30455-1-tiwai@suse.de


Signed-off-by: Takashi Iwai <tiwai@suse.de>