cgal,cgal-toolfile: add dependency on gmp-static and mpfr-static

Failures in Clang builds shows that CGAL actually needs to find GMP and
MPFR headers. Originally I compiled GMP and MPFR statically, then had
them as build time only dependency. The patch resolves Clang and ICC
build errors correctly.

There is already a partial fix on ICC:

    250dbe3a8d1df22f26eb625351c62d99ec629b02

Makes GMP and MPFR as 'Requires:' in CGAL. Then adds those dependencies
in CGAL toolfile.

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>