SDL: Fix warnings: static function, {} initializier, un-needed enum forward declaration

SDL Commits
1 
From dd6817b3b7b05ce12720b39b4c04a5ae92481677 Mon Sep 17 00:00:00 2001
From: Sylvain <[EMAIL REDACTED]>
Date: Tue, 23 Nov 2021 10:47:34 +0100
Subject: [PATCH] Fix warnings: static function, {} initializier, un-needed
 enum forward declaration

---
 src/core/linux/SDL_evdev_kbd.c     | 2 +-
 src/core/linux/SDL_threadprio.c    | 4 +++-
 src/video/wayland/SDL_waylanddyn.h | 3 ---
 3 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/core/linux/SDL_evdev_kbd.c b/src/core/linux/SDL_evdev_kbd.c
index 6792d8afdf8..75c33d3ea19 100644
--- a/src/core/linux/SDL_evdev_kbd.c
+++ b/src/core/linux/SDL_evdev_kbd.c
@@ -219,7 +219,7 @@ static void kbd_cleanup(void)
     ioctl(kbd->console_fd, KDSKBMODE, kbd->old_kbd_mode);
 }
 
-void
+static void
 SDL_EVDEV_kbd_reraise_signal(int sig)
 {
     raise(sig);
diff --git a/src/core/linux/SDL_threadprio.c b/src/core/linux/SDL_threadprio.c
index 0ee42c63161..73a9cd18be7 100644
--- a/src/core/linux/SDL_threadprio.c
+++ b/src/core/linux/SDL_threadprio.c
@@ -108,7 +108,9 @@ rtkit_initialize_realtime_thread()
     int nLimit = RLIMIT_RTTIME;
     pid_t nPid = 0; //self
     int nSchedPolicy = sched_getscheduler(nPid) | SCHED_RESET_ON_FORK;
-    struct sched_param schedParam = {};
+    struct sched_param schedParam;
+
+    SDL_zero(schedParam);
 
     // Requirement #1: Set RLIMIT_RTTIME
     err = getrlimit(nLimit, &rlimit);
diff --git a/src/video/wayland/SDL_waylanddyn.h b/src/video/wayland/SDL_waylanddyn.h
index 13b0884d076..aacfacf18e4 100644
--- a/src/video/wayland/SDL_waylanddyn.h
+++ b/src/video/wayland/SDL_waylanddyn.h
@@ -42,9 +42,6 @@ struct libdecor_state;
 struct libdecor_configuration;
 struct libdecor_interface;
 struct libdecor_frame_interface;
-enum libdecor_resize_edge;
-enum libdecor_capabilities;
-enum libdecor_window_state;
 
 #include <stdint.h>
 #include "wayland-cursor.h"