* dlfcn.cc (check_path_access): Call find_exec with FE_DLL option.

* path.h (enum fe_types): Add FE_DLL value.
	* spawn.cc (std_suffixes): Remove.
	(exe_suffixes): New suffix_info for executing files.
	(dll_suffixes): New suffix_info for searching shared libraries.
	(perhaps_suffix): Add opt argument.  Use dll_suffixes if FE_DLL
	option is given, exe_suffixes otherwise.
	(find_exec): Propagate opt argument to perhaps_suffix.  Drop suffix
	check when testing execute permission.
	(spawn_guts): Call perhaps_suffix with FE_NADA opt argument.

winsup/cygwin/path.h

@@ -266,7 +266,8 @@ enum fe_types
   FE_NADA = 0,		/* Nothing special */
   FE_NNF = 1,		/* Return NULL if not found */
   FE_NATIVE = 2,	/* Return native path in path_conv struct */
-  FE_CWD = 4		/* Search CWD for program */
+  FE_CWD = 4,		/* Search CWD for program */
+  FE_DLL = 8		/* Search for DLLs, not executables. */
 };
 const char * __stdcall find_exec (const char *name, path_conv& buf,
 				  const char *winenv = "PATH=",