[PATCH:xpr] Remove unneeded uses of <math.h> & -lm

[Gaetan Nadon]

On 13-11-16 02:05 AM, Alan Coopersmith wrote:
> Can't see why they were ever needed.
>
> Signed-off-by: Alan Coopersmith <alan.coopersmith at oracle.com>
> ---
>  Makefile.am |    2 +-
>  x2pmp.c     |    1 -
>  2 files changed, 1 insertion(+), 2 deletions(-)

If sqrt won't be used in the future (educated guess)
If all supported platforms have a correct C implementation of math
functions currently used

Reviewed-by: Gaetan Nadon <memsize at videotron.ca>