cue/load: revert: report when "tool" pkg is used in non-tool file

This reverts commit ca66319e39d5af71aa7ea665c3c449dbf9a17d78.

Reason for revert: will use different approach.

Change-Id: Ic0c3a9acbd0a9f213da6cc595f97081283a87a03
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/3900
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
diff --git a/cue/load/import.go b/cue/load/import.go
index 01bfe30..9fe0ca0 100644
--- a/cue/load/import.go
+++ b/cue/load/import.go
@@ -401,9 +401,6 @@
 			if !isTest || fp.c.Tests {
 				fp.imported[path] = append(fp.imported[path], spec.Pos())
 			}
-			if !isTool && strings.HasPrefix(path, "tool/") {
-				badFile(errors.Newf(spec.Pos(), "%s may only be imported in *_tool.cue files", quoted))
-			}
 		}
 	}
 	switch {
diff --git a/cue/load/loader_test.go b/cue/load/loader_test.go
index 94485ab..a7aa867 100644
--- a/cue/load/loader_test.go
+++ b/cue/load/loader_test.go
@@ -239,18 +239,6 @@
 root:   $CWD/testdata
 dir:    $CWD/testdata/toolonly
 display:./toolonly`,
-	}, {
-		cfg: &Config{
-			Dir: testdataDir,
-		},
-		args: args("./badtool"),
-		want: `
-err:    "tool/cli" may only be imported in *_tool.cue files
-path:   example.org/test/badtool:bad
-module: example.org/test
-root:   $CWD/testdata
-dir:    $CWD/testdata/badtool
-display:./badtool`,
 	}}
 	for i, tc := range testCases {
 		// if i != 5 {
diff --git a/cue/load/testdata/badtool/bad.cue b/cue/load/testdata/badtool/bad.cue
deleted file mode 100644
index 76c5a69..0000000
--- a/cue/load/testdata/badtool/bad.cue
+++ /dev/null
@@ -1,9 +0,0 @@
-package bad
-
-import "tool/cli"
-
-command foo task: {
-	foo: cli.Print & {
-		text: "foo"
-	}
-}