applicom.c: fix apparently-broken code in do_ac_read()

The code scriblles over a local pointer whereas it appears to be trying
to write to the memory at which that pointer points.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=11397



Nobody we know can test this change.

Reported-by: Zvonimir Rakamaric <zrakamar@cs.ubc.ca>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>