#104 %u for size_t shall be %zu

[Dilian Wesselinov Palauzov]

As of libexif 0.6.20,

libexif/canon/exif-mnote-data-canon.c:271 , libexif/fuji/exif-mnote-data-fuji.c:228, libexif/olympus/exif-mnote-data-olympus.c:486 and libexec/pentax/exif-mnote-data-pentax.c use %u to print size_t data. The correct way to print size_t is using %zu. On 64bit systems this makes difference.

Please replace in these files %u with %zu.