clang-tidy: Fix all remaining misc-include-cleaner violations

- Remove unused includes
- Add common false positive headers to misc-include-cleaner.IgnoreHeaders
- Add IWYU pragma keep for uncommon false positive headers

src/coredump/coredump-backtrace.c

@@ -10,8 +10,6 @@
 #include "format-util.h"
 #include "journal-importer.h"
 #include "log.h"
-#include "string-util.h"
-#include "user-util.h"
 
 int coredump_backtrace(int argc, char *argv[]) {
         _cleanup_(journal_importer_cleanup) JournalImporter importer = JOURNAL_IMPORTER_INIT(STDIN_FILENO);

src/coredump/coredump-context.c

@@ -3,7 +3,6 @@
 #include "sd-login.h"
 #include "sd-messages.h"
 
-#include "coredump-config.h"
 #include "coredump-context.h"
 #include "coredump-util.h"
 #include "dirent-util.h"

src/coredump/coredump-kernel-helper.c

@@ -10,7 +10,6 @@
 #include "coredump-util.h"
 #include "fd-util.h"
 #include "format-util.h"
-#include "iovec-wrapper.h"
 #include "log.h"
 #include "signal-util.h"
 

src/coredump/coredump-receive.c

@@ -8,7 +8,6 @@
 #include "coredump-submit.h"
 #include "iovec-util.h"
 #include "iovec-wrapper.h"
-#include "fd-util.h"
 #include "log.h"
 #include "socket-util.h"