Add missing fz_var() and fix potential memory leak.
Fix some compiler warnings on Android.

Use intptr_t when casting between a jlong and a pointer to suppress errors
about different size words.

Add a 'u' suffix to unsigned values output by the cmap dump utility.
Partially revert "Add missing fz_var() and fix potential memory leak."

(Revert the fix for potential memory leak - there wasn't a potential memory
leak as the device only takes ownership of it's display list if
dev->free_user is set).

This reverts commit ada560eb015e7b2208c492d47f28da8093733c4a.