Rebuild to split package.

Split into ambix{,-{lv2,standalone,vst}} to provide a package per plugin type/standalone.
Remove unneeded quotes and curly braces.
Do not rely on terrible script to create manifest.tll but call executable directly.
Adapt cmake calls to adhere to packaging guidelines.
Strip vst shared objects manually, as package_ambix-vst() won't do it for us.

PKGBUILD

@@ -3,7 +3,7 @@
 pkgname=ambix
 pkgname=(ambix ambix-{lv2,standalone,vst})
 pkgver=0.2.10
-pkgrel=3
+pkgrel=4
 pkgdesc="Ambisonic plug-ins with variable order for use in Digital Audio Workstations"
 arch=(x86_64)
 url="https://github.com/kronihias/ambix"