uml: move remaining useful contents of user_util.h

Rescue the useful contents of the soon-to-be-gone user-util.h.

pty.c now gets ptsname from stdlib.h like it should have always done.

CATCH_EINTR is now in os.h, although perhaps all usage should be under
os-Linux at some point.

get_pty is also in os.h.

This patch restores the old definition of ARRAY_SIZE in user.h.  This file is
included only in userspace files, so there will be no conflict with the
kernel's new ARRAY_SIZE.  The copy of the kernel's ARRAY_SIZE and associated
infrastructure is now gone.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/um/include/user.h

@@ -6,6 +6,14 @@
 #ifndef __USER_H__
 #define __USER_H__
 
+/*
+ * The usual definition - copied here because the kernel provides its own,
+ * fancier, type-safe, definition.  Using that one would require
+ * copying too much infrastructure for my taste, so userspace files
+ * get less checking than kernel files.
+ */
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+
 extern void panic(const char *fmt, ...)
 	__attribute__ ((format (printf, 1, 2)));
 extern int printk(const char *fmt, ...)
@@ -18,14 +26,3 @@ extern unsigned long strlcpy(char *, const char *, unsigned long);
 extern unsigned long strlcat(char *, const char *, unsigned long);
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */