[SCM] xwax/master: Add bindnow hardening, disable pie for performance reasons

[Daniel James]

Hi Jaromír,

> I didn't noticed any
> performance degradation.

Thanks, that's good to know. I've enabled all hardening options in
https://anonscm.debian.org/cgit/pkg-multimedia/xwax.git/commit/?id=0fb08b94d5a4a66ab44c580c8b16c1197c8be510

> And also no user complained.

That may not be proof of anything, especially if the user base for a
package is small.

I am unsure about how to enable parallel build, or if it is supported.
The doc https://www.debian.org/doc/debian-policy/ch-source.htm says to use:

DPKG_BUILD_OPTIONS=parallel=n

and in the note 27:

Packages built with make can often implement this by passing the -jn
option to make

...but doesn't suggest a reasonable value for n on Debian's build
servers. On a dual-core machine I could not find any obvious difference
when using a value of 2 for these parameters.

Cheers!

Daniel