gitignore: Add some missing artifacts for in-source build.

.gitignore

@@ -15,6 +15,10 @@ openxr_monado-dev.json
 openxr_monado.json
 src/xrt/compositor/shaders/*.vert.h
 src/xrt/compositor/shaders/*.frag.h
+src/xrt/targets/cli/monado-cli
+src/xrt/targets/gui/monado-gui
+src/xrt/targets/openxr/intermediate_manifest.json
+src/xrt/targets/targets_enabled_drivers.h
 
 # ignore build trees
 build/
@@ -29,3 +33,4 @@ build*/
 
 # Ignore patches generated by scripts
 patches/
+