remove some unused includes

Author: ludviggunne

Diff for: lib/checkers.cpp

@@ -20,7 +20,6 @@
 // python3 tools/get_checkers.py > lib/checkers.cpp
 
 #include "checkers.h"
-#include "utils.h"
 
 namespace checkers {
     const std::map<std::string, std::string> allCheckers{

Diff for: lib/checkers.h

@@ -24,7 +24,6 @@
 #include <vector>
 
 #include "config.h"
-#include "errortypes.h"
 
 namespace checkers {
     extern CPPCHECKLIB const std::map<std::string, std::string> allCheckers;

Diff for: lib/cppcheck.cpp

@@ -32,7 +32,6 @@
 #include "path.h"
 #include "platform.h"
 #include "preprocessor.h"
-#include "settings.h"
 #include "standards.h"
 #include "suppressions.h"
 #include "timer.h"
@@ -42,7 +41,6 @@
 #include "utils.h"
 #include "valueflow.h"
 #include "version.h"
-#include "checkers.h"
 
 #include <algorithm>
 #include <cassert>