Remove some unnecessary #ifdef directives

These directives are in files that are compiled only if the
symbols are defined.
* src/gfilenotify.c: Remove unnecessary ‘#ifdef HAVE_GFILENOTIFY’.
* src/inotify.c: Remove unnecessary ‘#ifdef HAVE_INOTIFY’.
* src/kqueue.c: Remove unnecessary ‘#ifdef HAVE_KQUEUE’.

src/gfilenotify.c

@@ -18,7 +18,6 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 
-#ifdef HAVE_GFILENOTIFY
 #include <stdio.h>
 #include <gio/gio.h>
 #include "lisp.h"
@@ -333,7 +332,4 @@ syms_of_gfilenotify (void)
   staticpro (&watch_list);
 
   Fprovide (intern_c_string ("gfilenotify"), Qnil);
-
 }
-
-#endif /* HAVE_GFILENOTIFY  */

src/inotify.c

@@ -19,8 +19,6 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 
-#ifdef HAVE_INOTIFY
-
 #include "lisp.h"
 #include "coding.h"
 #include "process.h"
@@ -550,5 +548,3 @@ syms_of_inotify (void)
 
   Fprovide (intern_c_string ("inotify"), Qnil);
 }
-
-#endif /* HAVE_INOTIFY */

src/kqueue.c

@@ -19,7 +19,6 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 
-#ifdef HAVE_KQUEUE
 #include <stdio.h>
 #include <sys/types.h>
 #include <sys/event.h>
@@ -533,8 +532,6 @@ syms_of_kqueue (void)
   Fprovide (intern_c_string ("kqueue"), Qnil);
 }
 
-#endif /* HAVE_KQUEUE  */
-
 /* PROBLEMS
    * https://bugs.launchpad.net/ubuntu/+source/libkqueue/+bug/1514837
      prevents tests on Ubuntu.  */