Update libm-test.inc comment about NaN signs [committed]

[Joseph Myers]

libm-test.inc has a comment about signs of NaNs not being tested.
This is out of date since:

commit ce66581742e7ae1d6ce59e5d2d4859b2ae41218c
Author: Joseph Myers <joseph@codesourcery.com>
Date:   Sat Nov 16 12:48:35 2013 +0000

    Test signs of NaNs in libm-test.inc where appropriate.

This patch removes the inaccurate statement.

Committed.

2016-05-18  Joseph Myers  <joseph@codesourcery.com>

	* math/libm-test.inc: Update comment not to refer to signs of NaNs
	not being tested.

diff --git a/math/libm-test.inc b/math/libm-test.inc
index f1ba7dd..b0451bd 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -80,8 +80,7 @@
    specified in ISO C99.
 
    NaN values: There exist signalling and quiet NaNs.  This implementation
-   only uses quiet NaN as parameter.  Where the sign of a NaN is
-   significant, this is not tested.  The payload of NaNs is not examined.
+   only uses quiet NaN as parameter.  The payload of NaNs is not examined.
 
    Inline functions: Inlining functions should give an improvement in
    speed - but not in precission.  The inlined functions return

-- 
Joseph S. Myers
joseph@codesourcery.com