Fix signedness mismatch
Fix signedness mismatch

This avoids warning C4018.

swaroop-sridhar/llilc,marksantos/llilc,adiaaida/llilc,kyulee1/llilcjit,russellhadley/llilc,AndyAyersMS/llilc,dotnet/llilc,swaroop-sridhar/llilc,swaroop-sridhar/llilc,manu-silicon/llilc,dkorolev/llilc,marksantos/llilc,marksantos/llilc,tempbottle/llilc,BruceForstall/llilc,dotnet/llilc,kyulee1/llilcjit,AndyAyersMS/llilc,manu-silicon/llilc,AndyAyersMS/llilc,adiaaida/llilc,JosephTremoulet/llilc,manu-silicon/llilc,kyulee1/llilcjit,russellhadley/llilc,JosephTremoulet/llilc,tempbottle/llilc,BruceForstall/llilc,dkorolev/llilc,dkorolev/llilc,adiaaida/llilc,russellhadley/llilc,dotnet/llilc,BruceForstall/llilc,tempbottle/llilc,JosephTremoulet/llilc