gpio.c: change check to allow fd 0
gpio.c: change check to allow fd 0

Signed-off-by: Jon Trulson <08664b19c2d4086eb239dd8ec32d593676a5b9e4@ics.com>
Signed-off-by: Brendan Le Foll <3e0e8c4069934e8b47d99704927a85c66c0ceb33@intel.com>

noahchense/mraa,w4ilun/mraa,zBMNForks/mraa,arunlee77/mraa,sergev/mraa,SyrianSpock/mraa,ProfFan/mraa,pctj101/mraa,ProfFan/mraa,SyrianSpock/mraa,noahchense/mraa,whbruce/mraa,noahchense/mraa,intel-iot-devkit/mraa,arfoll/mraa,zBMNForks/mraa,malikabhi05/mraa,arunlee77/mraa,Pillar1989/mraa,intel-iot-devkit/mraa,Hbrinj/mraa,KurtE/mraa,sergev/mraa,yongli3/mraa,alexandru-elisei/mraa,spitfire88/mraa,intel-iot-devkit/mraa,Kiritoalex/mraa,w4ilun/mraa,arunlee77/mraa,spitfire88/mraa,stefan-andritoiu/mraa-gpio-chardev,andreivasiliu2211/mraa,malikabhi05/mraa,alex1818/mraa,neuberfran/mraa,pctj101/mraa,neuberfran/mraa,sergev/mraa,Propanu/mraa,arunlee77/mraa,nioinnovation/mraa,andreivasiliu2211/mraa,alext-mkrs/mraa,arfoll/mraa,yongli3/mraa,tripzero/mraa,andreivasiliu2211/mraa,Meirtz/mraa,sundw2014/mraa,malikabhi05/mraa,Kiritoalex/mraa,intel-iot-devkit/mraa,yongli3/mraa,ncrastanaren/mraa,noahchense/mraa,Hbrinj/mraa,KurtE/mraa,sundw2014/mraa,alexandru-elisei/mraa,Pillar1989/mraa,whbruce/mraa,STANAPO/mraa,seem-sky/mraa,STANAPO/mraa,ncrastanaren/mraa,allela-roy/mraa,sergev/mraa,stefan-andritoiu/mraa-gpio-chardev,alext-mkrs/mraa,KurtE/mraa,yoyojacky/mraa,sundw2014/mraa,nioinnovation/mraa,SyrianSpock/mraa,jontrulson/mraa,sundw2014/mraa,ProfFan/mraa,petreeftime/mraa,alex1818/mraa,petreeftime/mraa,anonymouse64/mraa,tripzero/mraa,smileboywtu/mraa,sundw2014/mraa,ncrastanaren/mraa,timrtoo/Intel,STANAPO/mraa,g-vidal/mraa,mircea/mraa,jontrulson/mraa,Propanu/mraa,g-vidal/mraa,seem-sky/mraa,stefan-andritoiu/mraa,w4ilun/mraa,jontrulson/mraa,w4ilun/mraa,spitfire88/mraa,ncrastanaren/mraa,arfoll/mraa,andreivasiliu2211/mraa,stefan-andritoiu/mraa,neuroidss/mraa,malikabhi05/mraa,alext-mkrs/mraa,neuroidss/mraa,whbruce/mraa,Pillar1989/mraa,matt-auld/mraa,neuberfran/mraa,alex1818/mraa,anonymouse64/mraa,alexandru-elisei/mraa,yoyojacky/mraa,neuroidss/mraa,yoyojacky/mraa,smileboywtu/mraa,mircea/mraa,nioinnovation/mraa,timrtoo/Intel,smileboywtu/mraa,yongli3/mraa,yongli3/mraa,noahchense/mraa,allela-roy/mraa,mircea/mraa,stefan-andritoiu/mraa-gpio-chardev,Jon-ICS/mraa,Hbrinj/mraa,matt-auld/mraa,intel-iot-devkit/mraa,damcclos/mraa,stefan-andritoiu/mraa-gpio-chardev,timrtoo/Intel,alexandru-elisei/mraa,g-vidal/mraa,seem-sky/mraa,timrtoo/Intel,damcclos/mraa,Hbrinj/mraa,damcclos/mraa,pctj101/mraa,seem-sky/mraa,alexandru-elisei/mraa,pctj101/mraa,Propanu/mraa,stefan-andritoiu/mraa-gpio-chardev,Kiritoalex/mraa,spitfire88/mraa,Jon-ICS/mraa,Propanu/mraa,jontrulson/mraa,whbruce/mraa,pctj101/mraa,KurtE/mraa,g-vidal/mraa,alext-mkrs/mraa,neuberfran/mraa,arfoll/mraa,allela-roy/mraa,anonymouse64/mraa,g-vidal/mraa,jontrulson/mraa,KurtE/mraa,stefan-andritoiu/mraa,petreeftime/mraa,malikabhi05/mraa,Meirtz/mraa,neuberfran/mraa,petreeftime/mraa,Propanu/mraa,arfoll/mraa,ProfFan/mraa,stefan-andritoiu/mraa,alext-mkrs/mraa,stefan-andritoiu/mraa,tripzero/mraa,matt-auld/mraa,ncrastanaren/mraa,timrtoo/Intel,Meirtz/mraa,zBMNForks/mraa,Jon-ICS/mraa,seem-sky/mraa,sergev/mraa