platform/x86: asus-wireless: Fix uninitialized symbol usage

platform/x86: asus-wireless: Fix uninitialized symbol usage

BugLink: https://bugs.launchpad.net/bugs/1836287
[ Upstream commit eca4c4e47eb0658ad251f0bff465e23c055377da ]

'ret' will not be initialized if acpi_evaluate_integer() returns through
an error path, so it should not be used in this case. This fixes the
following Smatch static analyser error:

 drivers/platform/x86/asus-wireless.c:76 asus_wireless_method() error:
                                                     uninitialized symbol 'ret'.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: João Paulo Rechi Vita <jprvita@endlessm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>