cmd: remove superfluous if in eficonfig_edit_boot_option

Goto for an immediately succeeding label is superfluous.

Fixes: 87d79142 ("eficonfig: menu-driven addition of UEFI boot option")
Addresses-Coverity: 376202 ("Identical code for different branches")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>