Unify foreign import for vendor:sdl2

vendor/sdl2/sdl2.odin

@@ -26,11 +26,13 @@ import "core:c"
 import "core:intrinsics"
 
 when ODIN_OS == .Windows {
-	foreign import lib "SDL2.lib"
+	foreign import _lib "SDL2.lib"
 } else {
-	foreign import lib "system:SDL2"
+	foreign import _lib "system:SDL2"
 }
 
+lib :: _lib
+
 version :: struct {
 	major: u8,        /**< major version */
 	minor: u8,        /**< minor version */
@@ -45,7 +47,6 @@ PATCHLEVEL      :: 16
 foreign lib {
 	GetVersion  :: proc(ver: ^version) ---
 	GetRevision :: proc() -> cstring ---
-
 }
 
 InitFlag :: enum u32 {