libc: libstdc++: Rename vendor variant to libstdc++_vendor

* In Android 14, This library got listed on /vendor/etc/linker.config.pb,
  which is duplicated with /system/etc/linker.config.pb, as a result
  linkerconfig fails and stops the entire system from booting.

[    5.840677] DEBUG: Abort message: 'duplicate: libstdc++.so is provided by default and system in [vendor]'

Change-Id: Ib6eee48de87100c2fb0dd765d57ee95d3159c4ef
Signed-off-by: zlewchan <zlewchan@icloud.com>

libc/Android.bp

@@ -1915,7 +1915,7 @@ cc_library_headers {
 // libstdc++.so and libstdc++.a.
 // ========================================================
 
-cc_library {
+cc_defaults {
     defaults: ["libc_defaults"],
     include_dirs: ["bionic/libstdc++/include"],
     srcs: [
@@ -1923,13 +1923,12 @@ cc_library {
         "bionic/__cxa_pure_virtual.cpp",
         "bionic/new.cpp",
     ],
-    name: "libstdc++",
+    name: "libstdc++_defaults",
     static_ndk_lib: true,
     static_libs: ["libasync_safe"],
     apex_available: [
         "//apex_available:platform",
     ],
-    vendor_available: true,
 
     static: {
         system_shared_libs: [],
@@ -1967,6 +1966,17 @@ cc_library {
     },
 }
 
+cc_library {
+    name: "libstdc++",
+    defaults: ["libstdc++_defaults"],
+}
+
+cc_library_shared {
+    name: "libstdc++_vendor",
+    defaults: ["libstdc++_defaults"],
+    vendor: true,
+}
+
 genrule {
     name: "libstdc++.arm.map",
     out: ["libstdc++.arm.map.txt"],