Fix warning for Android NDK compiler: "function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]"

https://stackoverflow.com/questions/42125/warning-error-function-declaration-isnt-a-prototype
In C int foo() and int foo(void) are different functions. int foo() accepts an arbitrary number of arguments, while int foo(void) accepts 0 arguments. In C++ they mean the same thing.

src/test/SDL_test_memory.c

@@ -323,7 +323,7 @@ dbghelp_failed:
                            SDLTest_TrackedFree);
 }
 
-void SDLTest_RandFillAllocations()
+void SDLTest_RandFillAllocations(void)
 {
     SDLTest_TrackAllocations();