Fix px4_impl_os for protected build

For NuttX protected or kernel build, the prebuilds can't contain libraries which are
different for kernel and user-space in protected/kerenl builds

Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>

platforms/nuttx/cmake/px4_impl_os.cmake

@@ -177,7 +177,7 @@ function(px4_os_prebuild_targets)
 	endif()
 
 	add_library(prebuild_targets INTERFACE)
-	target_link_libraries(prebuild_targets INTERFACE nuttx_xx nuttx_c nuttx_fs nuttx_mm nuttx_sched m gcc)
+	target_link_libraries(prebuild_targets INTERFACE nuttx_xx m gcc)
 	add_dependencies(prebuild_targets DEPENDS nuttx_context uorb_headers)
 
 endfunction()