Handle arch-specific/not properties the same.

Refactor arch-handling code to return a "no-config" axis which allows
handling non-arch configed properties the same way as arch-configed
properties.

Test: build/bazel/ci/bp2build.sh
Change-Id: I485b35fd91c28501fe2055234dc9b278488bf4b5

android/arch.go

@@ -1967,6 +1967,7 @@ func (m *ModuleBase) GetArchVariantProperties(ctx ArchVariantContext, propertySe
 		srcType := reflect.ValueOf(generalProp).Type()
 		if srcType == dstType {
 			archProperties = m.archProperties[i]
+			axisToProps[bazel.NoConfigAxis] = ArchVariantProperties{"": generalProp}
 			break
 		}
 	}