[android] Put in fixes for librt and armv7-a

Android doesn't have a separate librt, it's just part of libc. Also, the static
build wasn't working for armv7-a, because the test executables wouldn't link
with the multiple definition errors listed in android/ndk#176, so use the
workaround given there.

Signed-off-by: Rokhini Prabhu <[email protected]>

Author: finagolfin

CMakeLists.txt

@@ -113,7 +113,9 @@ if(__BUILTIN_TRAP)
   set(HAVE_NORETURN_BUILTIN_TRAP 1)
 endif()
 
-find_package(LibRT)
+if(NOT CMAKE_SYSTEM_NAME STREQUAL Android)
+  find_package(LibRT)
+endif()
 
 check_function_exists(_pthread_workqueue_init HAVE__PTHREAD_WORKQUEUE_INIT)
 check_function_exists(getprogname HAVE_GETPROGNAME)