testing/php7-tideways_xhprof: enable on x86_64 only

testing/php7-tideways_xhprof/APKBUILD

@@ -5,10 +5,10 @@ _pkgext=tideways_xhprof
 _pkgreal=php-xhprof-extension
 pkgver=5.0_beta3
 _pkgver=${pkgver/_/-}
-pkgrel=3
+pkgrel=4
 pkgdesc="Modern XHProf compatible Profiler for PHP 7"
 url="http://tideways.io"
-arch="all !x86"
+arch="x86_64" # fails to build
 license="Apache-2.0"
 depends="php7"
 makedepends="php7-dev autoconf"