Add bionic support to endian.h

Bionic supports byteswap. Protobuf will support bionic in the near future,
which leads to macro-redefinition errors. Add recognition of bionic.

Bug: 72746797
Test: mmma external/libtextclassifier
Merged-In: I65cb7f0b067b68e3e1c22ee87232555887446089
Change-Id: I7fd9a1335a4b6cac51ab8e183d71a4e21ac59fee
diff --git a/util/base/endian.h b/util/base/endian.h
index f319f65..75f8bf7 100644
--- a/util/base/endian.h
+++ b/util/base/endian.h
@@ -40,7 +40,7 @@
 
 // The following guarantees declaration of the byte swap functions, and
 // defines __BYTE_ORDER for MSVC
-#if defined(__GLIBC__) || defined(__CYGWIN__)
+#if defined(__GLIBC__) || defined(__BIONIC__) || defined(__CYGWIN__)
 #include <byteswap.h>  // IWYU pragma: export
 // The following section defines the byte swap functions for OS X / iOS,
 // which does not ship with byteswap.h.