usb: gadget: f_uac1: remove an unneeded NULL check

This NULL check sets off a static checker warning because we already
dereferenced "card" earlier in the function.  However, since "card" is
never NULL so we can just remove the check.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Change-Id: Ic81cc20a9cdaee517eb18d1f2aed76e6b9cc877e
Git-commit: 60b388befb42d1e90a8594cdcfe80dbf57542ac0
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


[jackp@codeaurora.org: trivial conflict due to added pr_err()]
Signed-off-by: Jack Pham <jackp@codeaurora.org>