[PATCH] Use 1U everywhere in elf/elf.h.

[Roland McGrath]

It you're going to do it, you should be consistent and cover all the ones
that aren't written using << too.  (Every bare integer constant has type
int.)  Also, if this is important you should write a test for it.  I'm not
sure what is the easiest or best way to verify that a constant's type is
something in particular.  Note that the right type is not necessarily
something like 'unsigned int', but is a type whose signedness matches and
whose width is no larger than, the type of the corresponding struct field.

The test can use some scripting to grovel the full set of macro names to
test, with some hand-written rules for choosing the type (e.g. 'R_*' ->
'Elf32_Word').