s/master/main/

Test: treehugger
Change-Id: I2c975b2f5f92f23c7357b6f7e785578504298cc6
diff --git a/linker/linker.h b/linker/linker.h
index a803424..f5bb0ec 100644
--- a/linker/linker.h
+++ b/linker/linker.h
@@ -72,7 +72,7 @@
 };
 
 static constexpr const char* kBionicChangesUrl =
-    "https://android.googlesource.com/platform/bionic/+/master/"
+    "https://android.googlesource.com/platform/bionic/+/main/"
     "android-changes-for-ndk-developers.md";
 
 soinfo* get_libdl_info(const soinfo& linker_si);