libcheck: Fix do_install error with automake 1.18.1

libcheck: Fix do_install error with automake 1.18.1

Fixed do_install error with automake 1.18
$ makeinfo -I ../../check-0.15.2/doc -o ../../check-0.15.2/doc/check.info \
    ../../check-0.15.2/doc/check.texi
[snip]
check.texi:2329: no matching `@end verbatim'
[snip]

The automake before 1.17's mdate-sh couldn't update libcheck's
doc/version.texi, so the doc/check.info wasn't re-generated, then we couldn't
see the build error.

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>