[examples] Add drawing for generic gamepad on core_input_gamepad example

[asdqwe]

Gamepads detected as "generic" now look like this on the core_input_gamepad example:

To test this PR, spoof the aliases like this:

diff --git a/examples/core/core_input_gamepad.c b/examples/core/core_input_gamepad.c
index 538e1c38..e5af88f2 100644
--- a/examples/core/core_input_gamepad.c
+++ b/examples/core/core_input_gamepad.c
@@ -20,9 +20,9 @@
 #include "raylib.h"
 
 // NOTE: Gamepad name ID depends on drivers and OS
-#define XBOX_ALIAS_1 "xbox"
-#define XBOX_ALIAS_2 "x-box"
-#define PS_ALIAS     "playstation"
+#define XBOX_ALIAS_1 "aaa"
+#define XBOX_ALIAS_2 "bbb"
+#define PS_ALIAS     "ccc"
 
 //------------------------------------------------------------------------------------

[raysan5]

@asdqwe looks great! thanks! 😄