d/rules: build tests even if x86-64-v2 is not supported

If nocheck is not set, tests are always built but only run after
checking if the build CPU has all the x86-64-v2 features in the
override_dh_auto_test step.

debian/rules

@@ -32,19 +32,12 @@ ifeq ($(DEB_HOST_ARCH_CPU),amd64)
   export DEB_CXXFLAGS_MAINT_APPEND = -march=x86-64-v2
 endif
 
-test := true
 ifeq (,$(filter nocheck,$(DEB_BUILD_OPTIONS)))
-  ifeq ($(DEB_HOST_ARCH_CPU),amd64)
-    ifeq (,$(shell lscpu | awk '/cx16/ && /lahf/ && /popcnt/ && /sse3/ && /sse4_1/ && /sse4_2/ && /ssse3/'))
-      $(warning Your CPU doesn't support the x86-64-v2 micro-architecture level. Tests will be skipped.)
-      test := false
-    endif
-  endif
+  test := true
 else
   test := false
 endif
 
-
 ifeq (,$(filter noopt,$(DEB_BUILD_OPTIONS)))
   build_type := Release
   lto := true
@@ -80,5 +73,13 @@ override_dh_auto_configure:
 		-DCMAKE_INTERPROCEDURAL_OPTIMIZATION=$(lto) \
 		-DCMAKE_POLICY_DEFAULT_CMP0069=NEW
 
+override_dh_auto_test:
+	supports_x86_64_v2=$$(lscpu | awk '/cx16/ && /lahf/ && /popcnt/ && /sse3/ && /sse4_1/ && /sse4_2/ && /ssse3/' | tr -d '[:space:]') ; \
+	if [ '$(DEB_HOST_BUILD_CPU)' = amd64 ] && [ -z "$$supports_x86_64_v2" ]; then \
+		echo "Your CPU doesn't support the x86-64-v2 micro-architecture level. Tests will be skipped." ; \
+	else \
+		dh_auto_test ; \
+	fi
+
 execute_after_dh_auto_clean:
 	$(RM) externals/sirit