[bug#51358] [PATCH] Getting rid of some ocaml4.07-* packages.

[Julien Lepiller]

Hi Guix! this small patch series is a step forward to removing ocaml4.07
packages. There are a few leaf packages that still depend on ocaml
4.07, and this series takes care of fftw3, by building it with our
latest ocaml package (4.11, even though 4.13 is out; wip...).

The last patch is a bit messy. I didn't want to change to much from it,
but its source is no longer available. When testing the patch, guix was
able to use disarchive to get the content from SWH, but after a GC, and
one day, I am no longer able to download the sources. I know of the new
place, should I use it instead?

Trying to use Disarchive to assemble
/gnu/store/jxqnv4y2gyccsfhlbf1n7s5vn1rqgvxc-ocaml-charinfo-width-1.1.0.tar.gz...
Assembling the directory ocaml4.07-charinfo-width-1.1.0 Downloading
/gnu/store/jxqnv4y2gyccsfhlbf1n7s5vn1rqgvxc-ocaml-charinfo-width-1.1.0.tar.gz
from Software Heritage... tar extraction failure 32512 Could not
resolve directory reference failed to download
"/gnu/store/jxqnv4y2gyccsfhlbf1n7s5vn1rqgvxc-ocaml-charinfo-width-1.1.0.tar.gz"
from "https://bitbucket.org/zandoye/charinfo_width/get/1.1.0.tar.gz";
builder for
`/gnu/store/hshfvzxby5cfwmd5fzn8w82pxj525xjr-ocaml-charinfo-width-1.1.0.tar.gz.drv'
failed to produce output path
`/gnu/store/jxqnv4y2gyccsfhlbf1n7s5vn1rqgvxc-ocaml-charinfo-width-1.1.0.tar.gz'