• Fix build on amd64 (while not breaking build on i386)

Since time_t size is unspecified, the only way to print it correctly is by using %ld while casting the value to long

This is what upstream does for a long time:

https://github.com/facebook/watchman/commit/f2ec20fb2d98bfc9f54df43431564317de60429c

Approved by: portmgr blanket
MFH: 2015Q2