proxylib: Fix int conversion problem identified by CodeQL
proxylib: Fix int conversion problem identified by CodeQL

CodeQL identified "Incorrect conversion of a 64-bit integer from  to a
lower bit size type int without an upper bound check."

Signed-off-by: Tom Payne <96835dd8bfa718bd6447ccc87af89ae1675daeca@isovalent.com>

cilium/cilium,cilium/cilium,cilium/cilium,cilium/cilium,tklauser/cilium,tklauser/cilium,michi-covalent/cilium,michi-covalent/cilium,tklauser/cilium,cilium/cilium,tklauser/cilium,tklauser/cilium,michi-covalent/cilium,michi-covalent/cilium,michi-covalent/cilium