meson: drop intel_ prefix on imgui_core

Again, no real effect, just the name of a temporary build file.

Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>

src/imgui/meson.build

@@ -1,5 +1,5 @@
 libimgui_core = static_library(
-  'intel_imgui_core',
+  'imgui_core',
   files('imgui.cpp', 'imgui_draw.cpp', 'imgui_widgets.cpp'),
   cpp_args : ['-w'],
   install : false