cmd: provide command to display SMBIOS information

U-Boot can either generated an SMBIOS table or copy it from a prior boot
stage, e.g. QEMU.

Provide a command to display the SMBIOS information.

Currently only type 1 and 2 are translated to human readable text.
Other types may be added later. Currently only a hexdump and the list of
strings is provided for these.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

cmd/Makefile

@@ -168,6 +168,7 @@ obj-$(CONFIG_CMD_SETEXPR) += setexpr.o
 obj-$(CONFIG_CMD_SETEXPR_FMT) += printf.o
 obj-$(CONFIG_CMD_SPI) += spi.o
 obj-$(CONFIG_CMD_STRINGS) += strings.o
+obj-$(CONFIG_CMD_SMBIOS) += smbios.o
 obj-$(CONFIG_CMD_SMC) += smccc.o
 obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o
 obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o