Remove flag view_set_requested_frame_rate_mrr

It is already not in use

Flag: EXEMPT cleanup
Test: presubmit
Bug: 364706098
Change-Id: I3dd7e9f1b32ebe455504f815cb0f4944d295c974

Author: Rachel Lee

services/surfaceflinger/surfaceflinger_flags_new.aconfig

@@ -317,14 +317,6 @@ flag {
   }
 } # override_trusted_overlay
 
-flag {
-  name: "view_set_requested_frame_rate_mrr"
-  namespace: "core_graphics"
-  description: "Enable to use frame rate category NoPreference with fixed frame rate vote on MRR devices"
-  bug: "352206100"
-  is_fixed_read_only: true
-} # view_set_requested_frame_rate_mrr
-
 flag {
   name: "vrr_bugfix_24q4"
   namespace: "core_graphics"