internal/rosa: improve cmake interface

This should make the call site look better for new artifacts.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/cmake.go

@@ -38,14 +38,12 @@ make DESTDIR=/work install
 func init() { artifactsF[CMake] = Toolchain.newCMake }
 
 // CMakeAttr holds the project-specific attributes that will be applied to a new
-// [pkg.Artifact] compiled via CMake.
+// [pkg.Artifact] compiled via [CMake].
 type CMakeAttr struct {
 	// Path elements joined with source.
 	Append []string
 	// Use source tree as scratch space.
 	Writable bool
-	// Dependencies concatenated with the build system itself.
-	Extra []pkg.Artifact
 
 	// CMake CACHE entries.
 	Cache [][2]string
@@ -59,15 +57,16 @@ type CMakeAttr struct {
 	// Override the default installation prefix [AbsSystem].
 	Prefix *check.Absolute
 
-	// Return an exclusive artifact.
-	Exclusive bool
+	// Passed through to [Toolchain.New].
+	Flag int
 }
 
-// NewViaCMake returns a [pkg.Artifact] for compiling and installing via CMake.
+// NewViaCMake returns a [pkg.Artifact] for compiling and installing via [CMake].
 func (t Toolchain) NewViaCMake(
 	name, version, variant string,
 	source pkg.Artifact,
 	attr *CMakeAttr,
+	extra ...pkg.Artifact,
 ) pkg.Artifact {
 	if name == "" || version == "" || variant == "" {
 		panic("names must be non-empty")
@@ -95,13 +94,8 @@ chmod -R +w "${ROSA_SOURCE}"
 		prefix = AbsSystem
 	}
 
-	var flag int
-	if attr.Exclusive {
-		flag |= TExclusive
-	}
-
 	sourcePath := AbsUsrSrc.Append(name)
-	return t.New(name+"-"+variant+"-"+version, flag, stage3Concat(t, attr.Extra,
+	return t.New(name+"-"+variant+"-"+version, attr.Flag, stage3Concat(t, extra,
 		t.Load(CMake),
 		t.Load(Ninja),
 	), nil, slices.Concat([]string{