dl-elf.h: add some includes and fix comments

While there change the guard of the file

Signed-off-by: Peter S. Mazinger <ps.m@gmx.net>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

ldso/include/dl-elf.h

@@ -5,19 +5,21 @@
  * GNU Lesser General Public License version 2.1 or later.
  */
 
-#ifndef LINUXELF_H
-#define LINUXELF_H
+#ifndef _DL_ELF_H
+#define _DL_ELF_H
 
+#include <features.h>
+#include <bits/wordsize.h>
 #include <dl-string.h> /* before elf.h to get ELF_USES_RELOCA right */
 #include <elf.h>
 #include <link.h>
+#include <dl-defs.h>
 
-/* Forward declarations for stuff defined in ld_hash.h */
+/* Forward declarations for stuff defined in dl-hash.h */
 struct dyn_elf;
 struct elf_resolve;
 struct r_scope_elem;
 
-#include <dl-defs.h>
 #ifdef __LDSO_CACHE_SUPPORT__
 extern int _dl_map_cache(void);
 extern int _dl_unmap_cache(void);
@@ -29,7 +31,7 @@ static __inline__ void _dl_unmap_cache(void) { }
 #define DL_RESOLVE_SECURE		0x0001
 #define DL_RESOLVE_NOLOAD		0x0002
 
-/* Function prototypes for non-static stuff in readelflib1.c */
+/* Function prototypes for non-static stuff in elfinterp.c */
 extern void _dl_parse_lazy_relocation_information(struct dyn_elf *rpnt,
 	unsigned long rel_addr, unsigned long rel_size);
 extern int _dl_parse_relocation_information(struct dyn_elf *rpnt,
@@ -252,4 +254,4 @@ unsigned int __dl_parse_dynamic_info(ElfW(Dyn) *dpnt, unsigned long dynamic_info
 		    (((X) & PF_X) ? PROT_EXEC : 0))
 
 
-#endif	/* LINUXELF_H */
+#endif /* _DL_ELF_H */