libreprl: prefer `calloc` over `malloc` + `memset` (NFC) (#271)
libreprl: prefer `calloc` over `malloc` + `memset` (NFC) (#271)

This is a u-opt that simply aids in readability.  The compiler should be
able to merge the `malloc` + `memset` into `calloc`.
googleprojectzero/fuzzilli,googleprojectzero/fuzzilli,googleprojectzero/fuzzilli