Replace #apex with #systemapi

Currently, for an API symbol to be accessible to APEXes, it needs to be
marked as either # systemapi or # apex. It was originally just # apex,
but we added # systemapi to clearly identify the origin of the APIs.

The intended use is

* #apex is for APEX-visible symbols that are defined in an APEX
* #systemapi is for APEX-visible symbols that are defined in the
  platform (the non-updatable part)

This intention is documented build/soong/docs/map_files.md, but isn't
enforced at all.

With b/239274367, this is now enforced and therefore the #apex tags in
the platform library are replaced with `#systemapi`

This change does not alter any functionality.

Bug: 239274367
Test: m
Change-Id: I9075644877e9cf64b364edbcf5d07eef733c75dc
diff --git a/libs/nativewindow/libnativewindow.map.txt b/libs/nativewindow/libnativewindow.map.txt
index 988132c..da42a96 100644
--- a/libs/nativewindow/libnativewindow.map.txt
+++ b/libs/nativewindow/libnativewindow.map.txt
@@ -2,10 +2,10 @@
   global:
     AHardwareBuffer_acquire;
     AHardwareBuffer_allocate;
-    AHardwareBuffer_createFromHandle; # llndk # apex
+    AHardwareBuffer_createFromHandle; # llndk # systemapi
     AHardwareBuffer_describe;
     AHardwareBuffer_getId; # introduced=31
-    AHardwareBuffer_getNativeHandle; # llndk # apex
+    AHardwareBuffer_getNativeHandle; # llndk # systemapi
     AHardwareBuffer_isSupported; # introduced=29
     AHardwareBuffer_lock;
     AHardwareBuffer_lockAndGetInfo; # introduced=29
@@ -23,18 +23,18 @@
     ANativeWindow_getBuffersDataSpace; # introduced=28
     ANativeWindow_getFormat;
     ANativeWindow_getHeight;
-    ANativeWindow_getLastDequeueDuration; # apex # introduced=30
-    ANativeWindow_getLastDequeueStartTime; # apex # introduced=30
-    ANativeWindow_getLastQueueDuration; # apex # introduced=30
+    ANativeWindow_getLastDequeueDuration; # systemapi # introduced=30
+    ANativeWindow_getLastDequeueStartTime; # systemapi # introduced=30
+    ANativeWindow_getLastQueueDuration; # systemapi # introduced=30
     ANativeWindow_getWidth;
     ANativeWindow_lock;
     ANativeWindow_query; # llndk
     ANativeWindow_queryf; # llndk
     ANativeWindow_queueBuffer; # llndk
-    ANativeWindow_setCancelBufferInterceptor; # apex # introduced=30
-    ANativeWindow_setDequeueBufferInterceptor; # apex # introduced=30
-    ANativeWindow_setPerformInterceptor; # apex # introduced=30
-    ANativeWindow_setQueueBufferInterceptor; # apex # introduced=30
+    ANativeWindow_setCancelBufferInterceptor; # systemapi # introduced=30
+    ANativeWindow_setDequeueBufferInterceptor; # systemapi # introduced=30
+    ANativeWindow_setPerformInterceptor; # systemapi # introduced=30
+    ANativeWindow_setQueueBufferInterceptor; # systemapi # introduced=30
     ANativeWindow_release;
     ANativeWindow_setAutoPrerotation; # llndk
     ANativeWindow_setAutoRefresh; # llndk
@@ -45,7 +45,7 @@
     ANativeWindow_setBuffersGeometry;
     ANativeWindow_setBuffersTimestamp; # llndk
     ANativeWindow_setBuffersTransform;
-    ANativeWindow_setDequeueTimeout; # apex # introduced=30
+    ANativeWindow_setDequeueTimeout; # systemapi # introduced=30
     ANativeWindow_setFrameRate; # introduced=30
     ANativeWindow_setFrameRateWithChangeStrategy; # introduced=31
     ANativeWindow_setSharedBufferMode; # llndk