PR27716, build failure for msdosdjgpp: PATH_MAX undeclared

We shouldn't be using arbitrary limits like PATH_MAX in GNU programs.
This patch also fixes some memory leaks in readelf when processing
separate debug info.

	PR 27716
binutils/
	* objdump.c (show_line): Don't limit paths to PATH_MAX.
	* readelf.c (struct filedata): Change program_interpreter from
	a char array to a char pointer.
	(process_program_headers): Sanity check PT_INTERP p_filesz.
	Malloc program_interpreter using p_filesz and read directly from
	file.
	(process_dynamic_section): Check program_interpreter is non-NULL.
	(free_filedata): New function, split out from..
	(process_object): ..here.
	(close_debug_file): Call free_filedata.
	* sysdep.h: Don't include sys/param.h.
	(PATH_MAX): Don't define.
	* configure.ac: Don't check for sys/param.h.
	* configure: Regenerate.
gprof/
	* gprof.h (PATH_MAX): Don't define.
	* corefile.c (core_create_line_syms): Don't use PATH_MAX for initial
	file name size.
	* source.c (annotate_source): Malloc file name buffer.  Always
	trim off "-ann" when dos 8.3 annotate file matches original.
	* utils.c (print_name_only): Malloc file name buffer.

binutils/sysdep.h

@@ -124,23 +124,8 @@ extern char **environ;
 /* Used by ar.c and objcopy.c.  */
 #define BUFSIZE 8192
 
-/* For PATH_MAX.  */
 #include <limits.h>
 
-#ifndef PATH_MAX
-/* For MAXPATHLEN.  */
-# ifdef HAVE_SYS_PARAM_H
-#  include <sys/param.h>
-# endif
-# ifndef PATH_MAX
-#  ifdef MAXPATHLEN
-#   define PATH_MAX MAXPATHLEN
-#  else
-#   define PATH_MAX 1024
-#  endif
-# endif
-#endif
-
 #if SIZEOF_LONG_LONG > SIZEOF_LONG
 /* We can't use any bfd types here since readelf may define BFD64 and
    objdump may not.  */