Remove -fno-emulated-tls from linux_bionic

This was preventing tools using 'thread_local' from compiling and is
not needed. Bionic fully implements TLS.

Test: cd tools/dexter/slicer; mma
Bug: 31559095
Change-Id: Ib362ad8bc950726080356b61ccae83f155ce040b
diff --git a/cc/config/x86_linux_bionic_host.go b/cc/config/x86_linux_bionic_host.go
index 5fb88e6..fb1cdeb 100644
--- a/cc/config/x86_linux_bionic_host.go
+++ b/cc/config/x86_linux_bionic_host.go
@@ -124,7 +124,7 @@
 func (t *toolchainLinuxBionic) ToolchainClangCflags() string {
 	return "-m64 -march=x86-64" +
 		// TODO: We're not really android, but we don't have a triple yet b/31393676
-		" -U__ANDROID__ -fno-emulated-tls"
+		" -U__ANDROID__"
 }
 
 func (t *toolchainLinuxBionic) ToolchainClangLdflags() string {