binder_parcel_fuzzer: rlimit mem

In preparation for fixing TODOs here. The way that the fuzzer is setup,
if too big of allocations are made, they will fail, but it won't give
code a chance to handle it. So, setting rlimit to a lower value.

Bug: 131868573
Test: binder_parcel_fuzzer locally a bit
Change-Id: I840bdab8413024cd05f81587a99ebd07381e7fde