Include <sys/inotify.h> in the inotify_init probe, to avoid
an implicit function declaration.  Future compilers are likely
to reject implicit function declarations by default, making
the configure check invalid as written.

Fixed upstream via:

commit da4b42688a6cd5444eefb91bf40183d88203ffca
Author: Mojca Miklavec <mojca@macports.org>
Date:   Sat Nov 5 13:22:25 2022 +0100

    Fix implicit declaration configuration errors with Xcode 12
    
    Some configure could fail with errors like the following:
    
    conftest.c:56:33: error: implicitly declaring library function 'exit'
    with type 'void (int) __attribute__((noreturn))'
    [-Werror,-Wimplicit-function-declaration]
    
    See https://trac.macports.org/ticket/61672
    
    Closes #22946.


diff --git a/configure b/configure
index 54eb7a74f95d4dd2..232d202cc5da2345 100755
--- a/configure
+++ b/configure
@@ -37928,7 +37916,9 @@ if ${wx_cv_inotify_usable+:} false; then :
 else
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-int main() { return inotify_init(); }
+
+		    #include <sys/inotify.h>
+		    int main() { return inotify_init(); }
 _ACEOF
 if ac_fn_c_try_link "$LINENO"; then :
   wx_cv_inotify_usable=yes
diff --git a/configure.in b/configure.in
index c76c528f6635bece..bf6a33b3c10dc27a 100644
--- a/configure.in
+++ b/configure.in
@@ -5622,7 +5622,9 @@ if test "$wxUSE_FSWATCHER" = "yes"; then
                 [whether inotify is usable],
                 wx_cv_inotify_usable,
                 AC_LINK_IFELSE(
-                    [AC_LANG_SOURCE([int main() { return inotify_init(); }])],
+                    [AC_LANG_SOURCE([
+		    #include <sys/inotify.h>
+		    int main() { return inotify_init(); }])],
                     [wx_cv_inotify_usable=yes],
                     [wx_cv_inotify_usable=no]
                 )