sqrt.patch from bug #567

Using an old version of mingw-w64 (last updated May 2015),
calling sqrt(-1.0) would return NaN (the expected result).
After updating to the current version, it returns -1.0.

It looks like this bug was introduced by commit 6617eb.

Signed-off-by: Martin Whitaker <martinwhitaker@users.sf.net>
Signed-off-by: Kai Tietz <ktietz70@users.sf.net>
Signed-off-by: Jonathan Yong <10walls@gmail.com>