[preset] Build armv7k and i386 watch modules in package presets

After bumping the deployment target to watch 9+, these architectures are
no longer supported when building dylibs, but we can still build the
swiftmodule to support compiling for older platforms.

rdar://135560598

Author: benlangmuir

utils/build-presets.ini

@@ -1423,6 +1423,9 @@ darwin-toolchain-version=%(darwin_toolchain_version)s
 darwin-toolchain-alias=%(darwin_toolchain_alias)s
 darwin-toolchain-require-use-os-runtime=0
 
+# Build the swiftmodule/tbd for armv7k watchos and i386 watchsimulator.
+swift-darwin-module-archs=armv7k i386
+
 [preset: mixin_osx_package_test]
 build-subdir=buildbot_osx
 
@@ -2978,6 +2981,9 @@ swift-install-components=back-deployment;compiler;clang-builtin-headers;stdlib;l
 symbols-package=%(symbols_package)s
 install-symroot=%(install_symroot)s
 
+# Build the swiftmodule/tbd for armv7k watchos and i386 watchsimulator.
+swift-darwin-module-archs=armv7k i386
+
 [preset: source_compat_suite_linux_base]
 mixin-preset=source_compat_suite_base
 build-subdir=compat_linux