We added the explicit int64 casts for 32-bit builds in 35e1ad78 (Make
libpod build on 32-bit systems, 2018-02-12, #324), but the explicit
casts work fine on 64-bit systems too.
Signed-off-by: W. Trevor King <wking@tremily.us>
Closes: #1058
Approved by: mheon
W. Trevor King