cmd: allow packer-sdc fix on the SDK

Before this commit, `packer-sdc fix' would only work on plugins that
import the SDK, but we also need to make `packer-sdc fix' compatible
with the SDK itself, so we add an extra check to packer-sdc so it
doesn't ignore the SDK when applying the replace fix.

cmd/packer-sdc/internal/fix/gocty.go

@@ -67,7 +67,7 @@ func (f goCtyFix) fix(modFilePath string, data []byte) ([]byte, error) {
 
 	var requiresSDK, requiresGoCty bool
 	for _, req := range mf.Require {
-		if req.Mod.Path == sdkPath {
+		if req.Mod.Path == sdkPath || mf.Module.Mod.Path == sdkPath {
 			requiresSDK = true
 		}
 		if req.Mod.Path == f.OldPath {