Fix Eigen macros and flags to more closely match makepanda.py for Linux
Fix Eigen macros and flags to more closely match makepanda.py for Linux

-- EIGEN_MPL2_ONLY, EIGEN_NO_DEBUG needed to avoid array alignment assertions
-- -mtune=native/-march=native are not in makepanda and in gcc 4.x and 5.x, break float ABI ("tried to invert singular LMatrix4")

tobspr/P3DModuleBuilder,tobspr/P3DModuleBuilder,tobspr/P3DModuleBuilder