camlibs/ptp2: Unpack Canon EOS changes for INT32 properties
camlibs/ptp2: Unpack Canon EOS changes for INT32 properties

This datatype was missing in the change event unpacking code which caused the WhiteBalanceAdjust{A,B} properties to always read as 0 even though a different value was set on the camera.
Currently WhiteBalanceAdjust{A,B} are the only INT32 properties on Canon cameras.

gphoto/libgphoto2,gphoto/libgphoto2,gphoto/libgphoto2,gphoto/libgphoto2,gphoto/libgphoto2,gphoto/libgphoto2