[flang] - ieee_exceptions.f90: I added all of the routines listed in table 17.3...

[flang]  - ieee_exceptions.f90: I added all of the routines listed in table 17.3 of the standard that were not currently specified.  I also re-ordered the routines to be in the same order as the standard.
 - doconcurrent01.f90: I removed the custom versions of ieee_exceptions and
 iso_fortran_env.  I also fixed a typo in a comment.  Also, the use of the real
 standare interface caused one of the error messages to go away, so I fixed
 that.

Original-commit: flang-compiler/f18@a8b310a9685d7e6502073ecb011c16aaa1e1d14b
Reviewed-on: https://github.com/flang-compiler/f18/pull/637