fix(build): fix installing build tools for cross-compilation

'cmake --install . --component build-tools' copies no files [1]. This
was caused by commit 1f2e1a4 where the code calling install() became
dead code on accident. Call install() so that 'cmake --install' copies
the build artifacts as intended.

[1] #1099

Refs: 1f2e1a4

docs/CHANGELOG.md

@@ -6,6 +6,13 @@ based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 quick-lint-js' version numbers are arbitrary. quick-lint-js does *not* adhere to
 Semantic Versioning.
 
+## Unreleased
+
+### Fixed
+
+* `cmake --install` with `--component build-tools` now installs the build
+  tools. (This is a regression introduced in quick-lint-js version 2.16.0.)
+
 ## 2.17.0 (2023-10-25)
 
 [Downloads](https://c.quick-lint-js.com/releases/2.17.0/)

tools/CMakeLists.txt

@@ -68,7 +68,6 @@ if (QUICK_LINT_JS_ENABLE_BUILD_TOOLS)
     COMMENT "Building all quick-lint-js build-time tools"
     DEPENDS ${QUICK_LINT_JS_BUILD_TOOL_TARGETS}
   )
-elseif (QUICK_LINT_JS_ENABLE_BUILD_TOOLS)
   install(
     TARGETS ${QUICK_LINT_JS_BUILD_TOOL_TARGETS}
     COMPONENT build-tools