test: bdinfo: Handle systems without getopt

Systems without getopt support fall back to plain full bdinfo print,
handle such a case, which occurs e.g. with sandbox_flattree_defconfig .

Fixes: 8827a387 ("test: bdinfo: Test bdinfo -h")
Fixes: 2696f3ab ("test: bdinfo: Test bdinfo -m")
Fixes: 3ff2d796 ("test: bdinfo: Test bdinfo -e")
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>