configure: Restrict arm assembly to armv7 only.
configure: Restrict arm assembly to armv7 only.

ARM assembly in wavpack is armv7 only it seems.
I have reports this causes build failures on armv5: https://bugs.gentoo.org/show_bug.cgi?id=609168

dbry/WavPack,dbry/WavPack,dbry/WavPack