pccardctl: remove superfluous check

We can trust our own callers. Fixes:

 src/pccardctl.c:82: warning: the address of 'in_file' will always evaluate as 'true'

Reported-by: Alexander Mansurov <alexander.mansurov@gmail.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>