Convert disting of api txt from mk to bp

droidstubs dist now dists the api file, so convert these manual
mk rules into bp dist instead.

Bug: 149293194
Test: m dist sdk && find out/dist/apistubs -name /android\.txt
Change-Id: I96052b427dc01a6d24b040ad0006129d4d1e48fb

StubLibraries.bp

@@ -119,6 +119,11 @@ droidstubs {
             baseline_file: "api/lint-baseline.txt",
         },
     },
+    dist: {
+        targets: ["sdk", "win_sdk"],
+        dir: "apistubs/android/public/api",
+        dest: "android.txt",
+    },
     jdiff_enabled: true,
 }
 
@@ -160,6 +165,11 @@ droidstubs {
             baseline_file: "api/system-lint-baseline.txt",
         },
     },
+    dist: {
+        targets: ["sdk", "win_sdk"],
+        dir: "apistubs/android/system/api",
+        dest: "android.txt",
+    },
     jdiff_enabled: true,
 }
 
@@ -183,6 +193,11 @@ droidstubs {
             baseline_file: "api/test-lint-baseline.txt",
         },
     },
+    dist: {
+        targets: ["sdk", "win_sdk"],
+        dir: "apistubs/android/test/api",
+        dest: "android.txt",
+    },
 }
 
 /////////////////////////////////////////////////////////////////////
@@ -218,6 +233,11 @@ droidstubs {
             baseline_file: "api/module-lib-lint-baseline.txt",
         },
     },
+    dist: {
+        targets: ["sdk", "win_sdk"],
+        dir: "apistubs/android/module-lib/api",
+        dest: "android.txt",
+    },
 }