staging: bcm2835-audio: Fix memory corruption

staging: bcm2835-audio: Fix memory corruption

commit c97d96b4e612c7dc1b37d7afc61b598a9a25994d upstream.

The previous commit (0adbfd46) fixed a memory leak but also freed a
block in the success case, causing a stale pointer to be used with
potentially fatal results. Only free the vchi_instance block in the
case that vchi_connect fails; once connected, the instance is
retained for subsequent connections.

Simplifying the code by removing a bunch of gotos and returning errors
directly.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Fixes: 0adbfd4694c2 ("staging: bcm2835-audio: fix memory leak in bcm2835_audio_open_connection()")
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>