Revert "Fix warnings in linking tcmalloc"

This reverts commit a52bf9be78a5ef00804fe453154f47164b6bec8d.

Reason for revert: build breakage https://android-build.googleplex.com/builds/submitted/4988279/aosp_arm64-eng/latest/view/logs/build_error.log

Change-Id: I5d49a2f844f9f9d36f633052a7c3c2f59cbb9e4b
diff --git a/sysroot/usr/lib/libpthread.so b/sysroot/usr/lib/libpthread.so
index ca8dbee..f02ce72 100644
--- a/sysroot/usr/lib/libpthread.so
+++ b/sysroot/usr/lib/libpthread.so
@@ -2,4 +2,4 @@
    Use the shared library, but some functions are only in
    the static library, so try that secondarily.  */
 OUTPUT_FORMAT(elf64-x86-64)
-GROUP ( libpthread.so.0 libpthread.a )
+GROUP ( libpthread.so.0 libpthread_nonshared.a )