Cleanup add brace (#6545)

* Add braces after if conditions

* More add braces after if conditions

* Add braces after while() conditions

* Fix compilation because of macro being modified

* Add braces to for loop

* Add braces after if/goto

* Move comments up

* Remove extra () in the 'return ...;' statements

* More remove extra () in the 'return ...;' statements

* More remove extra () in the 'return ...;' statements after merge

* Fix inconsistent patterns are xxx == NULL vs !xxx

* More "{}" for "if() break;"  and "if() continue;"

* More "{}" after if() short statement

* More "{}" after "if () return;" statement

* More fix inconsistent patterns are xxx == NULL vs !xxx

* Revert some modificaion on SDL_RLEaccel.c

* SDL_RLEaccel: no short statement

* Cleanup 'if' where the bracket is in a new line

* Cleanup 'while' where the bracket is in a new line

* Cleanup 'for' where the bracket is in a new line

* Cleanup 'else' where the bracket is in a new line

(cherry picked from commit 6a2200823c to reduce conflicts merging between SDL2 and SDL3)

test/testerror.c

@@ -38,7 +38,7 @@ ThreadFunc(void *data)
         SDL_Delay(1 * 1000);
     }
     SDL_Log("Child thread error string: %s\n", SDL_GetError());
-    return (0);
+    return 0;
 }
 
 int
@@ -52,7 +52,7 @@ main(int argc, char *argv[])
     /* Load the SDL library */
     if (SDL_Init(0) < 0) {
         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
-        return (1);
+        return 1;
     }
 
     /* Set the error value for the main thread */
@@ -78,5 +78,5 @@ main(int argc, char *argv[])
     SDL_Log("Main thread error string: %s\n", SDL_GetError());
 
     SDL_Quit();
-    return (0);
+    return 0;
 }