chore: do not inject DXVA_Decoding trace category (#40891)

This doesn't need to be injected. Looks like it was an accident in
60ca38fb for https://github.com/electron/electron/pull/38465 .

patches/chromium/build_add_electron_tracing_category.patch

@@ -8,14 +8,13 @@ categories in use are known / declared.  This patch is required for us
 to introduce a new Electron category for Electron-specific tracing.
 
 diff --git a/base/trace_event/builtin_categories.h b/base/trace_event/builtin_categories.h
-index 0cc26b32992cbbd5f599e0e062dd5b22bbf6d2dc..fd6a0eebd004f9e92ba577d73dfa75f685476288 100644
+index 0cc26b32992cbbd5f599e0e062dd5b22bbf6d2dc..2bc3fea0bc469a0cf26fa2a5af9c404294078f4a 100644
 --- a/base/trace_event/builtin_categories.h
 +++ b/base/trace_event/builtin_categories.h
-@@ -82,6 +82,8 @@
+@@ -82,6 +82,7 @@
    X("drm")                                                               \
    X("drmcursor")                                                         \
    X("dwrite")                                                            \
-+  X("DXVA_Decoding")                                                     \
 +  X("electron")                                                          \
    X("evdev")                                                             \
    X("event")                                                             \