[APInt] Remove the mul/urem/srem/udiv/sdiv functions from the APIntOps namespace. Replace the few usages with calls to the class methods. NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299292 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Support/APInt.cpp

@@ -881,7 +881,7 @@ APInt llvm::APIntOps::GreatestCommonDivisor(const APInt& API1,
   APInt A = API1, B = API2;
   while (!!B) {
     APInt T = B;
-    B = APIntOps::urem(A, B);
+    B = A.urem(B);
     A = T;
   }
   return A;