Add install-llvm to WebAssembly presets

Author: MaxDesiatov

utils/build-presets.ini

@@ -2463,6 +2463,7 @@ install-prefix=/%(TOOLCHAIN_NAME)s/usr
 swift-install-components=autolink-driver;compiler;clang-builtin-headers;stdlib;sdk-overlay;parser-lib;editor-integration;tools;testsuite-tools;toolchain-tools;license;sourcekit-inproc;swift-remote-mirror;swift-remote-mirror-headers;clang-resource-dir-symlink
 llvm-install-components=clang
 install-swift
+install-llvm
 darwin-toolchain-bundle-identifier=%(BUNDLE_IDENTIFIER)s
 darwin-toolchain-display-name=%(DISPLAY_NAME)s
 darwin-toolchain-display-name-short=%(DISPLAY_NAME_SHORT)s