[Lapack] confusing comment in blacs, dgamx2d_.c and dgamn2d_.c

[Ake Sandgren]

The comment
"If rdest == -1, then CDEST ignored."
is a bit confusing since the code is the other way around, i.e. if cdest
== -1 then rdest is ignored.

-- 
Ake Sandgren, HPC2N, Umea University, S-90187 Umea, Sweden
Internet: ake@Domain.Removed   Phone: +46 90 7866134 Fax: +46 90 7866126
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