[GPU Service] Name GPU service back to "gpu"

Changed the GPU service name back to be compatible with external
engines/tools' usage of vkjson cmd.

Bug: 118347356
Test: adb shell cmd gpu vkjson
Change-Id: I8830149e6f239d95a7397329ba2f8bc99561d494
diff --git a/services/gpuservice/gpuservice.rc b/services/gpuservice/gpuservice.rc
index d23cf46..65a5c27 100644
--- a/services/gpuservice/gpuservice.rc
+++ b/services/gpuservice/gpuservice.rc
@@ -1,4 +1,4 @@
-service gpuservice /system/bin/gpuservice
+service gpu /system/bin/gpuservice
     class core
     user gpu_service
     group graphics