[Macros] Add the correct RPATH flags to the in-process plugin server host library

Also, make sure it builds for Android.

Author: finagolfin

tools/swift-plugin-server/CMakeLists.txt

@@ -25,6 +25,7 @@ if (SWIFT_BUILD_SWIFT_SYNTAX)
     set_property(TARGET SwiftInProcPluginServer
       APPEND PROPERTY INSTALL_RPATH
         "$ORIGIN")
+    _set_pure_swift_link_flags(SwiftInProcPluginServer "../../")
   endif()
 
   # FXIME: Importing package-cmo enabled '.swiftmodule' causes compiler crash :(

tools/swift-plugin-server/Sources/SwiftInProcPluginServer/InProcPluginServer.swift

@@ -17,6 +17,8 @@
 import Darwin
 #elseif canImport(Glibc)
 import Glibc
+#elseif canImport(Bionic)
+import Bionic
 #elseif canImport(Musl)
 import Musl
 #elseif canImport(ucrt)