api: Fix broken build on ARM.

This patch fixes broken build introduced by commit
84bf7ca522e94ec402a1264b01971b924b7e268f (api: remove un-needed
ifdef CONFIG_API already handle by the Makefile).

Signed-off-by: Piotr Ziecik <kosmo@semihalf.com>
diff --git a/api/api_platform-arm.c b/api/api_platform-arm.c
index fffaa1e..e65a180 100644
--- a/api/api_platform-arm.c
+++ b/api/api_platform-arm.c
@@ -53,5 +53,3 @@
 
 	return 1;
 }
-
-#endif /* CONFIG_API */