[PATCH, libgfortran] Fix PR21875 (FM111.f) BN and BZ format

[Andrew Pinski]

> The attached patches fix the problems in libgfortran and revise the test 
> case to include a test of the snippet similar to the SPECfp problem with 
> trailing blanks in exponents.
> 
> Regression tested (excluding real_const_1.f90, real_const_2.f90, and 
> elemental.f90, which are failing from something else).
> 
> 2005-07-19  Jerry DeLisle  <jvdelisle@verizon.net>
> 
> * io/read.c (read_f): Fix reading of trailing blanks in   	exponents 
> related to BZ and BN format specifier logic.
> * io/unit.c (init_units): Change default setting of u->flags.blank
> to BLANK_UNSPECIFIED for stdin, stdout, and stderr.
> 
> OK to commit to mainline and 4.0?

I just want to say thanks for looking into this problem.

-- Pinski