C# bindings: Added public functions Device.reg_read / Device.reg_write
C# bindings: Added public functions Device.reg_read / Device.reg_write

Signed-off-by: Paul Cercueil <73d292422978d45c9eeef455bb1b24a0db453722@analog.com>

sensarliar/libiio,gburca/libiio,gburca/libiio,analogdevicesinc/libiio,Sunderfield/libiio,analogdevicesinc/libiio,Sunderfield/libiio,gburca/libiio,analogdevicesinc/libiio,Sunderfield/libiio,analogdevicesinc/libiio,sensarliar/libiio,sensarliar/libiio