SDL: x11: get x1/x2 button state in GetGlobalMouseState

SDL Commits
1 
From 3fcc2cb500a752698687ad0c8bb14778e6cb84c3 Mon Sep 17 00:00:00 2001
From: emily <[EMAIL REDACTED]>
Date: Tue, 3 May 2022 11:19:39 +0200
Subject: [PATCH] x11: get x1/x2 button state in GetGlobalMouseState

---
 src/video/x11/SDL_x11mouse.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/video/x11/SDL_x11mouse.c b/src/video/x11/SDL_x11mouse.c
index 9eb1ddd3075..4d741acad20 100644
--- a/src/video/x11/SDL_x11mouse.c
+++ b/src/video/x11/SDL_x11mouse.c
@@ -406,6 +406,8 @@ X11_GetGlobalMouseState(int *x, int *y)
                     buttons |= (mask & Button1Mask) ? SDL_BUTTON_LMASK : 0;
                     buttons |= (mask & Button2Mask) ? SDL_BUTTON_MMASK : 0;
                     buttons |= (mask & Button3Mask) ? SDL_BUTTON_RMASK : 0;
+                    buttons |= (mask & Button4Mask) ? SDL_BUTTON_X1MASK : 0;
+                    buttons |= (mask & Button5Mask) ? SDL_BUTTON_X2MASK : 0;
                     /* SDL_DisplayData->x,y point to screen origin, and adding them to mouse coordinates relative to root window doesn't do the right thing
                      * (observed on dual monitor setup with primary display being the rightmost one - mouse was offset to the right).
                      *