processor: Move ftrace parsing and descriptors to importers/ftrace

In preparation of aosp/1146725

Bug: 141459049
Change-Id: Icbb1379646222aed95c389818195f1f5e44ea919
diff --git a/Android.bp b/Android.bp
index 513d4cc..3380421 100644
--- a/Android.bp
+++ b/Android.bp
@@ -4545,19 +4545,19 @@
     "src/trace_processor/event_tracker.cc",
     "src/trace_processor/filtered_row_index.cc",
     "src/trace_processor/forwarding_trace_parser.cc",
-    "src/trace_processor/ftrace_descriptors.cc",
     "src/trace_processor/ftrace_utils.cc",
     "src/trace_processor/graphics_event_parser.cc",
     "src/trace_processor/gzip_trace_parser.cc",
     "src/trace_processor/heap_graph_tracker.cc",
     "src/trace_processor/heap_profile_allocation_table.cc",
     "src/trace_processor/heap_profile_tracker.cc",
+    "src/trace_processor/importers/ftrace/ftrace_descriptors.cc",
+    "src/trace_processor/importers/ftrace/ftrace_parser.cc",
+    "src/trace_processor/importers/ftrace/ftrace_tokenizer.cc",
     "src/trace_processor/importers/fuchsia/fuchsia_provider_view.cc",
     "src/trace_processor/importers/fuchsia/fuchsia_trace_parser.cc",
     "src/trace_processor/importers/fuchsia/fuchsia_trace_tokenizer.cc",
     "src/trace_processor/importers/fuchsia/fuchsia_trace_utils.cc",
-    "src/trace_processor/importers/proto/ftrace_parser.cc",
-    "src/trace_processor/importers/proto/ftrace_tokenizer.cc",
     "src/trace_processor/importers/systrace/systrace_parser.cc",
     "src/trace_processor/importers/systrace/systrace_trace_parser.cc",
     "src/trace_processor/instants_table.cc",