Modifies CMake Config to export FMA build flags
Modifies CMake Config to export FMA build flags

This allows projects that link against Chrono to read the '-mfma' flag
required for gcc and clang to use FMA libraries. For example, this
allows the chrono-projects repository to build against chrono with
chrono-parallel and chrono-opengl enabled, using out-of-box brew
versions of GLM. Without this fix the build will not use FMA and fail.

dariomangoni/chrono,tjolsen/chrono,armanpazouki/chrono,amelmquist/chrono,projectchrono/chrono,dariomangoni/chrono,amelmquist/chrono,jcmadsen/chrono,tjolsen/chrono,jcmadsen/chrono,rserban/chrono,dariomangoni/chrono,jcmadsen/chrono,rserban/chrono,jcmadsen/chrono,rserban/chrono,dariomangoni/chrono,Milad-Rakhsha/chrono,armanpazouki/chrono,rserban/chrono,dariomangoni/chrono,armanpazouki/chrono,jcmadsen/chrono,projectchrono/chrono,dariomangoni/chrono,rserban/chrono,amelmquist/chrono,armanpazouki/chrono,tjolsen/chrono,Milad-Rakhsha/chrono,amelmquist/chrono,projectchrono/chrono,tjolsen/chrono,amelmquist/chrono,armanpazouki/chrono,projectchrono/chrono,rserban/chrono,Milad-Rakhsha/chrono,amelmquist/chrono,projectchrono/chrono,projectchrono/chrono,armanpazouki/chrono,tjolsen/chrono,jcmadsen/chrono,Milad-Rakhsha/chrono,Milad-Rakhsha/chrono,jcmadsen/chrono,rserban/chrono,Milad-Rakhsha/chrono