USER-DPD: more whitespace fixes

src/USER-DPD/compute_dpd_atom.cpp

src/USER-DPD/fix_eos_table_rx.cpp

src/USER-DPD/fix_rx.cpp

src/USER-DPD/npair_half_bin_newton_ssa.cpp

src/USER-DPD/npair_halffull_newton_ssa.cpp

src/USER-DPD/npair_halffull_newton_ssa.h

src/USER-DPD/nstencil_half_bin_2d_newton_ssa.cpp

src/USER-DPD/nstencil_half_bin_3d_newton_ssa.cpp

src/USER-DPD/pair_dpd_fdt.cpp

src/USER-DPD/pair_multi_lucy.cpp