Revert "Make bionic_platform_headers available only for Bionic t..."

Reason for revert: Breaks rvc-d1-dev-plus-aosp: http://ab/6443190
Reverted Changes:
Ide447b89a:bionic_libc_platform_headers is only available whe...
Ia93cd3ec8:bionic_libc_platform_headers is only available whe...
Icdc495588:Make bionic_platform_headers available only for Bi...
Idfd7c87dc:bionic_libc_platform_headers is only available whe...

Bug: 152255951
Bug: 155269399
Change-Id: I214f1165bb0a7e59d3b35a13b3cceb1965be922b
diff --git a/libc/Android.bp b/libc/Android.bp
index b2ba2c3..f73ae4a 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -1751,7 +1751,6 @@
 // Headers that only other parts of the platform can include.
 cc_library_headers {
     name: "bionic_libc_platform_headers",
-    defaults: ["linux_bionic_supported"],
     visibility: [
         "//art:__subpackages__",
         "//bionic:__subpackages__",
@@ -1763,6 +1762,7 @@
         "//system/core/libunwindstack:__subpackages__",
         "//system/memory/libmemunreachable:__subpackages__",
     ],
+    host_supported: true,
     vendor_available: true,
     ramdisk_available: true,
     recovery_available: true,
diff --git a/tests/Android.bp b/tests/Android.bp
index 75fdd90..c751084 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -22,12 +22,6 @@
         darwin: {
             enabled: false,
         },
-        android: {
-            header_libs: ["bionic_libc_platform_headers"],
-        },
-        linux_bionic: {
-            header_libs: ["bionic_libc_platform_headers"],
-        },
     },
     cflags: [
         "-fstack-protector-all",
@@ -44,6 +38,7 @@
         // For glibc.
         "-D__STDC_LIMIT_MACROS",
     ],
+    header_libs: ["bionic_libc_platform_headers"],
     // Ensure that the tests exercise shadow call stack support and
     // the hint space PAC/BTI instructions.
     arch: {
diff --git a/tests/mte_test.cpp b/tests/mte_test.cpp
index ff8cde6..8928805 100644
--- a/tests/mte_test.cpp
+++ b/tests/mte_test.cpp
@@ -14,10 +14,6 @@
  * limitations under the License.
  */
 
-#include <sys/cdefs.h>
-
-#if defined(__BIONIC__)
-
 #include <gtest/gtest.h>
 
 #include <android-base/macros.h>
@@ -50,5 +46,3 @@
 TEST(mte_test, ScopedDisableMTE) {
   test_tag_mismatch();
 }
-
-#endif  // __BIONIC__
diff --git a/tests/utils.h b/tests/utils.h
index a9b8513..5085a7a 100644
--- a/tests/utils.h
+++ b/tests/utils.h
@@ -25,11 +25,7 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
-#if defined(__BIONIC__)
 #include <bionic/macros.h>
-#else
-#define untag_address(p) p
-#endif
 
 #include <atomic>
 #include <string>