Address some cppcheck complaints

Author: martinhsv

examples/multiprocess_c/multi.c

@@ -97,7 +97,6 @@ int main (int argc, char **argv)
 {
     int ret;
     const char *error = NULL;
-    int i = 0;
     pid_t pid;
     int f;
 

src/engine/lua.cc

@@ -329,7 +329,6 @@ int Lua::setvar(lua_State *L) {
     std::string collection;
     std::string variableName;
     int nargs = lua_gettop(L);
-    char *chr = NULL;
     size_t pos;
     void *z(NULL);
 

test/cppcheck_suppressions.txt

@@ -64,6 +64,7 @@ passedByValue:src/variables/global.h:110
 passedByValue:src/parser/driver.cc:45
 passedByValue:test/common/modsecurity_test.cc:49
 passedByValue:test/common/modsecurity_test.cc:98
+unreadVariable:src/rule_with_operator.cc:219
 
 uninitvar:src/operators/verify_cpf.cc:77
 uninitvar:src/operators/verify_svnr.cc:67
@@ -91,7 +92,6 @@ cstyleCast
 functionStatic
 variableScope
 shadowFunction
-unreadVariable
 
 
 // Examples

test/optimization/optimization.cc

@@ -83,7 +83,6 @@ int main(int argc, char **argv) {
 
         for (int i = 0; i < rules->size(); i++) {
             auto z = rules->at(i);
-            std::string key;
             if (z == NULL) {
                 continue;
             }
@@ -95,7 +94,6 @@ int main(int argc, char **argv) {
                 } else {
                     operators[op] = 1;
                 }
-                key = op;
             }
 
             if (dynamic_cast<modsecurity::RuleWithOperator *>(z.get()) != nullptr) {
@@ -107,7 +105,6 @@ int main(int argc, char **argv) {
                 } else {
                     operators[op] = 1;
                 }
-                key = op;
             }
 
         }