um: Mark get_top_address as __init

It's only invoked during boot from linux_main().

Signed-off-by: Tiwei Bie <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Johannes Berg <[email protected]>

Author: btw616

arch/um/kernel/um_arch.c

@@ -289,7 +289,7 @@ static void __init parse_cache_line(char *line)
 	}
 }
 
-static unsigned long get_top_address(char **envp)
+static unsigned long __init get_top_address(char **envp)
 {
 	unsigned long top_addr = (unsigned long) &top_addr;
 	int i;