remove x86_64-linux-glibc2.11-4.8 prebuilt

Bug: b/73539603
Test: ./toolchain/mingw/build.sh
diff --git a/default.xml b/default.xml
index d91c3cd..06dc630 100644
--- a/default.xml
+++ b/default.xml
@@ -8,7 +8,6 @@
            remote="aosp"
            sync-j="4" />
 
-  <project path="prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.11-4.8" name="platform/prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.11-4.8" groups="pdk,linux" />
   <project path="prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.15-4.8" name="platform/prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.15-4.8" groups="pdk,linux" />
   <project path="toolchain/binutils" name="toolchain/binutils" />
   <project path="toolchain/cloog" name="toolchain/cloog" />