systemtap: upgrade 4.8 -> 4.9

SystemTap 4.9 release went out with a little hick up: release date was not
set correctly and fix for it was added as ebb424eee5599fcc131901c0d82d0bfc0d2f57ab
commit and tagged as 'release-4.9'. Unfortunately by that time 'master'
branch already has moved on, and it turns out that now 'release-4.9' tag does
not belong to any branch. On other hand OE SRC_URI does complain about git
uri without branch. To deal with it we will use SRCREV set to
418f0a45ca4473491385b5c7eef777607bbdb3b7, commit one that precedes
ebb424eee5599fcc131901c0d82d0bfc0d2f57ab, and add separate patch for
ebb424eee5599fcc131901c0d82d0bfc0d2f57ab as 0001-release-date-fix.patch.

Note for any future version move: please remove 0001-release-date-fix.patch

Signed-off-by: Victor Kamensky <victor.kamensky7@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>