lib/: run_command(): Use ATTR_ACCESS() instead of /*@out@*/

Link: <https://splint.org/manual/manual.html#undefined>
Cc: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

lib/spawn.c

@@ -17,8 +17,9 @@
 
 #include "shadowlog_internal.h"
 
-int run_command (const char *cmd, const char *argv[],
-                 /*@null@*/const char *envp[], /*@out@*/int *status)
+int
+run_command(const char *cmd, const char *argv[],
+            /*@null@*/const char *envp[], int *status)
 {
 	pid_t pid, wpid;