Fix build a chec failures after b05fae4d8e

The include cleanup on dl-minimal.c removed too much for some
targets.

Also for Hurd, __sbrk is removed from localplt.data now that
tunables allocated memory through mmap.

Checked with a build for all affected architectures.

elf/dl-minimal.c

@@ -23,6 +23,8 @@
 #include <dl-sym-post.h>
 #include <_itoa.h>
 #include <dl-minimal-malloc.h>
+#include <stdio.h>
+#include <unistd.h>
 
 
 /* The rtld startup code calls __rtld_malloc_init_stubs after the