app-antivirus/clamav: new revision fixing libtool -> libltdl depend.

app-antivirus/clamav: new revision fixing libtool -> libltdl depend.

As reported in bug 544910, libclamav is linked against libltdl.so:

  $ objdump -p /usr/lib64/libclamav.so | grep NEEDED
  NEEDED               libbz2.so.1
  NEEDED               libltdl.so.7
  ...

and that library is provided by dev-libs/libltdl:

  $ equery b /usr/lib64/libltdl.so.7
   * Searching for /usr/lib64/libltdl.so.7 ...
  dev-libs/libltdl-2.4.6 (/usr/lib64/libltdl.so.7.3.1)
  dev-libs/libltdl-2.4.6 (/usr/lib64/libltdl.so.7 -> libltdl.so.7.3.1)

We've been pulling this in "accidentally," through sys-devel/libtool,
but that's incorrect. This commit drops sys-devel/libtool and replaces
it with dev-libs/libltdl.

Closes: https://bugs.gentoo.org/544910
Package-Manager: Portage-2.3.79, Repoman-2.3.16
Signed-off-by: Michael Orlitzky <mjo@gentoo.org>