[imgui] Set C++ 11 standard in CMakeLists.txt (#25601)

* [imgui] Enable C++ 11 standard as code requires it

see vcpkg issue microsoft#25588

* [imgui] Enable C++ 11 standard using target_compile_features

As lerppana suggested:
It is better to use cxx_std_11 meta feature instead of locking the version number.
This should indicate cmake to use at least 11 instead of exactly 11.

see vcpkg issue microsoft#25588

* [imgui] update versions (vcpkg x-add-version imgui)

Enable C++ 11 standard as code requires it

see vcpkg issue microsoft#25588

ports/imgui/CMakeLists.txt

@@ -28,6 +28,8 @@ target_sources(
         ${CMAKE_CURRENT_SOURCE_DIR}/misc/cpp/imgui_stdlib.cpp
 )
 
+target_compile_features(${PROJECT_NAME} PUBLIC cxx_std_11)
+
 if(IMGUI_BUILD_ALLEGRO5_BINDING)
     find_path(ALLEGRO5_INCLUDE_DIRS allegro5/allegro.h)
     target_include_directories(${PROJECT_NAME} PRIVATE ${ALLEGRO5_INCLUDE_DIRS})

ports/imgui/vcpkg.json

@@ -1,6 +1,7 @@
 {
   "name": "imgui",
   "version": "1.88",
+  "port-version": 1,
   "description": "Bloat-free Immediate Mode Graphical User interface for C++ with minimal dependencies.",
   "homepage": "https://github.com/ocornut/imgui",
   "license": "MIT",

versions/baseline.json

@@ -2966,7 +2966,7 @@
     },
     "imgui": {
       "baseline": "1.88",
-      "port-version": 0
+      "port-version": 1
     },
     "imgui-sfml": {
       "baseline": "2.5",

versions/i-/imgui.json

@@ -1,5 +1,10 @@
 {
   "versions": [
+    {
+      "git-tree": "2a4c55df4b895535fba9e3934ed64cef92bf4a4d",
+      "version": "1.88",
+      "port-version": 1
+    },
     {
       "git-tree": "c28ebbdbe22a87ce01c3b2b6c15bed036721c6a0",
       "version": "1.88",