d/rules: cleanup cruft and use dpkg makefile fragements

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

debian/rules

@@ -1,22 +1,12 @@
 #!/usr/bin/make -f
 # -*- makefile -*-
-# Sample debian/rules that uses debhelper.
-# This file was originally written by Joey Hess and Craig Small.
-# As a special exception, when this file is copied by dh-make into a
-# dh-make output file, you may use that output file without restriction.
-# This special exception was added by Craig Small in version 0.37 of dh-make.
 
 # Uncomment this to turn on verbose mode.
 #export DH_VERBOSE=1
 
-include /usr/share/dpkg/pkg-info.mk
+include /usr/share/dpkg/default.mk
 
-# These are used for cross-compiling and for saving the configure script
-# from having to guess our platform (since we know it already)
-DEB_HOST_GNU_TYPE   ?= $(shell dpkg-architecture -qDEB_HOST_GNU_TYPE)
-DEB_BUILD_GNU_TYPE  ?= $(shell dpkg-architecture -qDEB_BUILD_GNU_TYPE)
-
-ARCH ?= $(shell dpkg-architecture -qDEB_HOST_GNU_CPU)
+HOST_CPU ?= $(DEB_HOST_GNU_CPU)
 
 PACKAGE=pve-qemu-kvm
 destdir := $(CURDIR)/debian/$(PACKAGE)
@@ -61,7 +51,7 @@ endif
 	--localstatedir=/var \
 	--prefix=/usr \
 	--sysconfdir=/etc \
-	--target-list=$(ARCH)-softmmu,aarch64-softmmu \
+	--target-list=$(HOST_CPU)-softmmu,aarch64-softmmu \
 	--with-suffix="kvm" \
 	--with-pkgversion="${DEB_SOURCE}_${DEB_VERSION_UPSTREAM_REVISION}" \
 	--audio-drv-list="alsa" \