common-user: Only compile the common user code if have_user is set

There is no need to waste cycles here if we only compile the system
binaries or tools. Additionally, this change is even a hard requirement
for building the tools on systems that do not have an entry in the
common-user/host/ folder (since common-user/meson.build is trying
to add such a path via the include_directories() command).

Reported-by: Michael Tokarev <[email protected]>
Signed-off-by: Thomas Huth <[email protected]>
Reviewed-by: Zhang Chen <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Laurent Vivier <[email protected]>

Author: huth

common-user/meson.build

@@ -1,3 +1,7 @@
+if not have_user
+   subdir_done()
+endif
+
 common_user_inc += include_directories('host/' / host_arch)
 
 user_ss.add(files(