Add "generic" fallback.

gcc warned that the function may not have a return value, indeed
for non-intel and non-amd X86 CPUs it is right (VIA, etc.).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91276 91177308-0d34-0410-b5e6-96231b3b80d8

lib/System/Host.cpp

@@ -292,6 +292,7 @@ std::string sys::getHostCPUName() {
       return "generic";
     }
   }
+  return "generic";
 }
 #else
 std::string sys::getHostCPUName() {