ALSA: echoaudio: add a check for ioremap_nocache

[ Upstream commit 6ade657d6125ec3ec07f95fa51e28138aef6208f ]

In case ioremap_nocache fails, the fix releases chip and returns
an error code upstream to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>