webservices: Use a long double variable in format_double.

[Sebastian Lackner]

On 11.07.2016 09:46, Hans Leidekker wrote:
> Signed-off-by: Hans Leidekker <hans at codeweavers.com>
> ---
>  configure.ac              |  1 +
>  dlls/webservices/writer.c | 21 ++++++++++++++-------
>  2 files changed, 15 insertions(+), 7 deletions(-)
> 

Signed-off-by: Sebastian Lackner <sebastian at fds-team.de>