x86: Don't process the kernel command line unless enabled

If the 'bootm' command is not enabled then this code is not available and
this causes a link error. Fix it.

Note that for the EFI app, there is no indication of missing code. It just
hangs!

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
1 file changed