Revert "Name function arguments in libc headers for Studio."

This reverts commit 079bff4fa52b0c3c76057451cc9cdecf1827fce0.

Broke builds with SANITIZE_HOST=address with an asan failure in versioner.

Change-Id: I22b113fd5405589d1a25e5e137c450aaba1ade5f
diff --git a/libc/include/sys/reboot.h b/libc/include/sys/reboot.h
index c0c4860..df4739e 100644
--- a/libc/include/sys/reboot.h
+++ b/libc/include/sys/reboot.h
@@ -42,8 +42,8 @@
 #define RB_DISABLE_CAD  LINUX_REBOOT_CMD_CAD_OFF
 #define RB_POWER_OFF    LINUX_REBOOT_CMD_POWER_OFF
 
-int reboot(int __cmd);
+int reboot(int reboot_type);
 
 __END_DECLS
 
-#endif
+#endif /* _SYS_REBOOT_H_ */