[lapack-reference] Fix missing link libraries in pc file.

[Neumann-A]

pkgconfig files for lapack needs to add implicitly linked Fortran libraries.
Otherwise the pc file is not useable in C/CXX projects.

(Link errors observed in paraview through dlib, dlib uses pkgconfig to find lapack and is thus missing the -lgfortran flags etc)

Resulting pc file:

prefix=${pcfiledir}/../..
libdir=${prefix}/lib
includedir=${prefix}/include

Name: LAPACK
Description: FORTRAN reference implementation of LAPACK Linear Algebra PACKage
Version: 3.12.0
URL: http://www.netlib.org/lapack/

Libs: "-L${libdir}" -llapack -lgfortran -lquadmath -lm
Requires: blas

Previously:

prefix=${pcfiledir}/../..
libdir=${prefix}/lib
includedir=${prefix}/include

Name: LAPACK
Description: FORTRAN reference implementation of LAPACK Linear Algebra PACKage
Version: 3.12.0
URL: http://www.netlib.org/lapack/

Libs: "-L${libdir}" -llapack
Requires: blas