ALSA: usb-audio: Add error checks against get_min_max*()

ALSA: usb-audio: Add error checks against get_min_max*()

All callers of get_min_max*() ignore the latter's return code
completely. This means to ignore temporary errors at the probe time.
However, it is not optimal and leads to some maintenance burdens.

Return -EAGAIN for temporary errors, and check against it in the callers
of get_min_max*(). If any other error occurs, bail out of the caller
early.

Suggested-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/87ldewi4j8.wl-tiwai@suse.de
Signed-off-by: Rong Zhang <i@rong.moe>
Link: https://patch.msgid.link/20260411-uac-sticky-mixer-v1-1-29d62717befd@rong.moe
Signed-off-by: Takashi Iwai <tiwai@suse.de>