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

test/testdisplayinfo.c

@@ -19,8 +19,9 @@
 static void
 print_mode(const char *prefix, const SDL_DisplayMode *mode)
 {
-    if (!mode)
+    if (mode == NULL) {
         return;
+    }
 
     SDL_Log("%s: fmt=%s w=%d h=%d refresh=%d\n",
             prefix, SDL_GetPixelFormatName(mode->format),