staging: ft1000: ft1000-usb: ft1000_hw.c: Fix a potential memory leak.

Avoid allocate memory if we will exit the function.

Was found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>