Android support (apple#163)

Author: marcprux

Sources/Instrumentation/Locks.swift

@@ -30,6 +30,8 @@
 import Darwin
 #elseif canImport(Glibc)
 import Glibc
+#elseif canImport(Android)
+import Android
 #elseif canImport(Musl)
 import Musl
 #else

Sources/Tracing/TracingTime.swift

@@ -19,6 +19,8 @@
 import Darwin
 #elseif canImport(Glibc)
 import Glibc
+#elseif canImport(Android)
+import Android
 #elseif canImport(Musl)
 import Musl
 #else

Tests/TracingTests/TracerTests.swift

@@ -18,7 +18,7 @@ import XCTest
 
 @testable @_spi(Locking) import Instrumentation
 
-#if os(Linux)
+#if os(Linux) || os(Android)
 @preconcurrency import Dispatch
 #endif