Fix pow (0.0, -Inf) (bug 14241)

[David Miller]

From: "Joseph S. Myers" <joseph@codesourcery.com>
Date: Thu, 14 Jun 2012 20:57:08 +0000 (UTC)

> 2012-06-14  Joseph Myers  <joseph@codesourcery.com>
> 
> 	[BZ #14241]
> 	* sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Use 0.0 instead
> 	of ABS(x) in calculating zero to negative powers other than odd
> 	integers.
> 	* math/libm-test.inc (pow_test): Add more tests.

Just FYI, I've successfully regstrapped this on sparcv9-*-linux
and sparc64-*-linux.