Details:
- Added set of basic scalar macros that take arguments' real and
imaginary components separately, named like the previous set except
with the "ris" (instead of "s") suffix.
- Redefined the previous set of scalar macros (those that take arguments
"whole") in terms of the new "ri" set.
- Renamed setris and getris macros to sets and gets.
- Renamed setimag0 macros to seti0s.
- Use bli_?1 macro instead of a local constant in bla_trmv.c, bla_trsv.c.