gnu: SuiteSparse: Update to 5.7.1.

gnu: SuiteSparse: Update to 5.7.1.

* gnu/packages/maths.scm (suitesparse): Update to 5.7.1.
[source]: The latest releases of SuiteSparse have only been published on GitHub.
Fetch from git tag as GitHub releases page only contains autogenerated tarballs
that guix lint complains about. Apply new patch for Mongoose's CMakeList.txt to
find SuiteSparse_config.
[arguments]: Add CMake flags used by new components GraphBLAS and Mongoose.
[native-inputs]: Add CMake and m4 needed to build GraphBLAS and Mongoose.
* gnu/packages/patches/suitesparse-mongoose-cmake.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.

Signed-off-by: Leo Famulari <leo@famulari.name>