AM: inline and re-indent if (.true.) body
AM: rm trailing whitespace
AM: use resp_util_module, only: ... where needed

There is also a larger block of comments reformatted
AM: revert the commits 7d0cbd5..d653651

It appears that at least for ./qa/au-tddft/i.h2o input that chage
leads to poor convergence. One of the sympthomes is the low CHMIX
value of 0.03 for many iterations.

By git diff 7d0cbd5..d653651 modules/mixing_module.f90 | patch -p1