Define bench-models as static library in CMake

Object libraries can't have dependencies in new CMake versions

PiperOrigin-RevId: 284821021
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3a7c387..51a9fd4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2045,7 +2045,7 @@
   TARGET_LINK_LIBRARIES(f32-sigmoid-eval PRIVATE XNNPACK benchmark fp16)
 
   # ---[ Build end-to-end microbenchmarks
-  ADD_LIBRARY(bench-models OBJECT
+  ADD_LIBRARY(bench-models STATIC
     models/mobilenet-v1.cc
     models/mobilenet-v2.cc
     models/mobilenet-v3-large.cc