Lower minimum version for swift binary

CMake apparently doesn't do anything with CMAKE_OSX_DEPLOYMENT_TARGET
for swift, which results in a 12+ minimum version.  This fixes it
(albeit in a hacky way since the only apple-sanctioned way to properly
set this appears to be "use xcode").

Shame on Apple, as usual.

daemon/CMakeLists.txt

@@ -2,6 +2,7 @@ set(exetargets lokinet)
 
 if(APPLE)
   add_executable(lokinet lokinet.swift)
+  target_compile_options(lokinet BEFORE PRIVATE -target x86_64-apple-macos${CMAKE_OSX_DEPLOYMENT_TARGET})
 else()
   add_executable(lokinet lokinet.cpp)
 endif()

daemon/lokinet.swift

@@ -87,7 +87,9 @@ class LokinetMain: NSObject, NSApplicationDelegate {
             providerProtocol.serverAddress = "loki.loki" // Needs to be set to some non-null dummy value
             providerProtocol.username = "anonymous"
             providerProtocol.providerBundleIdentifier = self.netextBundleId
-            providerProtocol.enforceRoutes = true
+            if #available(macOS 11, *) {
+                providerProtocol.enforceRoutes = true
+            }
             // macos seems to have trouble when this is true, and reports are that this breaks and
             // doesn't do what it says on the tin in the first place.  Needs more testing.
             providerProtocol.includeAllNetworks = false