Patch for bz#11589 - jn calculation

[David Miller]

From: Andreas Schwab <schwab@redhat.com>
Date: Tue, 27 Sep 2011 14:27:55 +0200

> ldbl-128ibm uses the same j0 and j1 implementation as ldbl-128 because
> it "looks like we can".  
> 
> Doesn't linux-sparc use ldbl-128?  If so, does the j0 and j1
> implementation provide enough precision for these tests?

I've been getting getting testsuite failures on sparc in this area
ever since the powerpc changes went in.