remove unused "syscall.h" includes

libc/stdio/remove.c

 #include <stdio.h>
 #include <errno.h>
 #include <unistd.h>
-#include "syscall.h"
 
 int remove(const char *path)
 {

libc/stdio/tmpnam.c

@@ -4,7 +4,6 @@
 #include <unistd.h>
 #include <time.h>
 #include "libc.h"
-#include "syscall.h"
 #include "atomic.h"
 
 #define MAXTRIES 100