Do not pass "-pie" in cflags

Bug: http://b/111000555

It's only needed for linking and Android already passes this by default.
Passing it to a compile step causes clang to emit
-Wunused-command-line-argument.

Test: build
Change-Id: Iea608387a57f0a65cfc3e67ab19c8d812f4aef37

test/Android.bp

@@ -27,7 +27,6 @@ cc_test {
         "-DARM",
         "-DMD5_DISABLE",
         "-fPIC",
-        "-pie",
         "-Wall",
         "-Werror",
         "-Wno-unused-variable",